Add initial mail sync range selection

Wino.Core.Domain/Entities/Shared/MailAccount.cs

@@ -112,6 +112,16 @@ public class MailAccount
     /// </summary>
     public DateTime? LastFolderStructureSyncDate { get; set; }
 
+    /// <summary>
+    /// Gets or sets when the account was created in Wino.
+    /// </summary>
+    public DateTime? CreatedAt { get; set; }
+
+    /// <summary>
+    /// Gets or sets the timespan used for the account's initial mail synchronization.
+    /// </summary>
+    public InitialSynchronizationRange InitialSynchronizationRange { get; set; } = InitialSynchronizationRange.SixMonths;
+
     /// <summary>
     /// Gets whether the account can perform ProfileInformation sync type.
     /// </summary>

Wino.Core.Domain/Enums/InitialSynchronizationRange.cs

@@ -0,0 +1,10 @@
+namespace Wino.Core.Domain.Enums;
+
+public enum InitialSynchronizationRange
+{
+    SixMonths = 0,
+    ThreeMonths = 1,
+    NineMonths = 2,
+    OneYear = 3,
+    Everything = 4
+}

Wino.Core.Domain/Extensions/InitialSynchronizationRangeExtensions.cs

@@ -0,0 +1,23 @@
+using System;
+using Wino.Core.Domain.Enums;
+
+namespace Wino.Core.Domain.Extensions;
+
+public static class InitialSynchronizationRangeExtensions
+{
+    public static DateTime? ToCutoffDateUtc(this InitialSynchronizationRange range, DateTime utcNow)
+    {
+        var normalizedUtcNow = utcNow.Kind == DateTimeKind.Utc
+            ? utcNow
+            : utcNow.ToUniversalTime();
+
+        return range switch
+        {
+            InitialSynchronizationRange.ThreeMonths => normalizedUtcNow.AddMonths(-3),
+            InitialSynchronizationRange.SixMonths => normalizedUtcNow.AddMonths(-6),
+            InitialSynchronizationRange.NineMonths => normalizedUtcNow.AddMonths(-9),
+            InitialSynchronizationRange.OneYear => normalizedUtcNow.AddYears(-1),
+            _ => null
+        };
+    }
+}

Wino.Core.Domain/Models/Accounts/AccountCreationDialogResult.cs

@@ -1,5 +1,10 @@
-using Wino.Core.Domain.Enums;
+using Wino.Core.Domain.Enums;
 
 namespace Wino.Core.Domain.Models.Accounts;
 
-public record AccountCreationDialogResult(MailProviderType ProviderType, string AccountName, SpecialImapProviderDetails SpecialImapProviderDetails, string AccountColorHex);
+public record AccountCreationDialogResult(
+    MailProviderType ProviderType,
+    string AccountName,
+    SpecialImapProviderDetails SpecialImapProviderDetails,
+    string AccountColorHex,
+    InitialSynchronizationRange InitialSynchronizationRange);

Wino.Core.Domain/Models/Accounts/InitialSynchronizationRangeOption.cs

@@ -0,0 +1,17 @@
+using Wino.Core.Domain.Enums;
+
+namespace Wino.Core.Domain.Models.Accounts;
+
+public sealed class InitialSynchronizationRangeOption
+{
+    public InitialSynchronizationRange Range { get; }
+    public string DisplayText { get; }
+
+    public bool IsEverything => Range == InitialSynchronizationRange.Everything;
+
+    public InitialSynchronizationRangeOption(InitialSynchronizationRange range, string displayText)
+    {
+        Range = range;
+        DisplayText = displayText;
+    }
+}

Wino.Core.Domain/Translations/en_US/resources.json

@@ -23,6 +23,14 @@
     "AccountCreationDialog_Initializing": "initializing",
     "AccountCreationDialog_PreparingFolders": "We are getting folder information at the moment.",
     "AccountCreationDialog_SigninIn": "Account information is being saved.",
+    "AccountCreation_InitialSynchronization_Title": "Mail synchronization range",
+    "AccountCreation_InitialSynchronization_Description": "Choose how far back Wino should download your mail during the first synchronization.",
+    "AccountCreation_InitialSynchronization_3Months": "3 Months",
+    "AccountCreation_InitialSynchronization_6Months": "6 Months",
+    "AccountCreation_InitialSynchronization_9Months": "9 Months",
+    "AccountCreation_InitialSynchronization_Year": "Year",
+    "AccountCreation_InitialSynchronization_Everything": "Everything",
+    "AccountCreation_InitialSynchronization_EverythingWarning": "This will synchronize all your mails to your computer. Extensive use of disk storage is needed. This is not recommended. For optimal performance use smaller synchronization timespan and use online search to access your mails.",
     "Purchased": "Purchased",
     "AccountEditDialog_Message": "Account Name",
     "AccountEditDialog_Title": "Edit Account",
@@ -37,6 +45,8 @@
     "AccountDetailsPage_TabMail": "Mail",
     "AccountDetailsPage_TabCalendar": "Calendar",
     "AccountDetailsPage_CalendarListDescription": "Select a calendar to configure its settings",
+    "AccountDetailsPage_InitialSynchronization_Title": "Initial synchronization",
+    "AccountDetailsPage_InitialSynchronization_Description": "Wino synchronized your mails until {0} going back.",
     "AddHyperlink": "Add",
     "AppCloseBackgroundSynchronizationWarningTitle": "Background Synchronization",
     "AppCloseStartupLaunchDisabledWarningMessageFirstLine": "Application has not been set to launch on Windows startup.",

Wino.Core/Synchronizers/GmailSynchronizer.cs

@@ -81,9 +81,8 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
     public override uint BatchModificationSize => 1000;
 
     /// <summary>
-    /// Maximum messages to fetch per folder during initial sync (1500).
+    /// Legacy page size hint kept for compatibility with shared synchronizer contracts.
-    /// All messages are downloaded with METADATA ONLY - no raw MIME content.
+    /// Gmail initial sync now downloads all messages inside the selected cutoff window.
-    /// Uses Gmail API's Metadata format which includes headers, labels, and snippet but NOT full message body.
     /// </summary>
     public override uint InitialMessageDownloadCountPerFolder => 1500;
 
@@ -304,13 +303,18 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
 
     /// <summary>
     /// Performs initial synchronization by downloading messages per-folder.
-    /// Each folder gets up to 1500 messages, but we track already downloaded message IDs globally
+    /// Messages are filtered by the account's configured initial synchronization cutoff date when present,
-    /// to avoid downloading the same message multiple times (Gmail messages can have multiple labels).
+    /// and duplicates are avoided globally because Gmail messages can have multiple labels.
     /// </summary>
     private async Task<List<string>> PerformInitialSyncAsync(CancellationToken cancellationToken)
     {
         // Track all downloaded message IDs globally to avoid duplicate downloads
         var downloadedMessageIds = new HashSet<string>();
+        var referenceDateUtc = Account.CreatedAt ?? DateTime.UtcNow;
+        var initialSynchronizationCutoffDateUtc = Account.InitialSynchronizationRange.ToCutoffDateUtc(referenceDateUtc);
+        var queryText = initialSynchronizationCutoffDateUtc.HasValue
+            ? $"after:{initialSynchronizationCutoffDateUtc.Value.ToUniversalTime():yyyy/MM/dd}"
+            : null;
 
         _logger.Information("Performing initial sync for {Name} - downloading messages per folder", Account.Name);
 
@@ -337,7 +341,6 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
 
                 var folderDownloaded = 0;
                 string pageToken = null;
-                var remainingToDownload = (int)InitialMessageDownloadCountPerFolder;
 
                 do
                 {
@@ -345,8 +348,9 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
 
                     var request = _gmailService.Users.Messages.List("me");
                     request.LabelIds = new Google.Apis.Util.Repeatable<string>(new[] { folder.RemoteFolderId });
-                    request.MaxResults = Math.Min(remainingToDownload, 500); // API max is 500
+                    request.MaxResults = 500; // API max is 500
                     request.PageToken = pageToken;
+                    request.Q = queryText;
 
                     var response = await request.ExecuteAsync(cancellationToken);
 
@@ -373,19 +377,12 @@ public class GmailSynchronizer : WinoSynchronizer<IClientServiceRequest, Message
                             totalMessagesDownloaded += newMessageIds.Count;
                         }
 
-                        // Count all messages (including duplicates) toward the folder limit
-                        remainingToDownload -= response.Messages.Count;
-
                         _logger.Debug("Folder {FolderName}: Downloaded {New} new messages ({Total} total in folder)",
                             folder.FolderName, newMessageIds.Count, folderDownloaded);
                     }
 
                     pageToken = response.NextPageToken;
 
-                    // Stop if we've processed enough messages for this folder or no more pages
-                    if (remainingToDownload <= 0 || string.IsNullOrEmpty(pageToken))
-                        break;
-
                 } while (!string.IsNullOrEmpty(pageToken));
 
                 _logger.Information("Folder {FolderName}: Downloaded {Count} messages", folder.FolderName, folderDownloaded);

Wino.Core/Synchronizers/ImapSync/UnifiedImapSynchronizer.cs

@@ -9,6 +9,7 @@ using MailKit.Search;
 using MoreLinq;
 using Serilog;
 using Wino.Core.Domain.Entities.Mail;
+using Wino.Core.Domain.Extensions;
 using Wino.Core.Domain.Enums;
 using Wino.Core.Domain.Interfaces;
 using Wino.Core.Domain.Models.MailItem;
@@ -252,9 +253,20 @@ public class UnifiedImapSynchronizer
                 .OpenAsync(FolderAccess.ReadOnly, folder.UidValidity, localHighestModSeq, knownUidStructs, cancellationToken)
                 .ConfigureAwait(false);
 
-            var changedUids = await remoteFolder
+            IList<UniqueId> changedUids;
-                .SearchAsync(SearchQuery.ChangedSince(localHighestModSeq), cancellationToken)
+
-                .ConfigureAwait(false);
+            if (folder.HighestModeSeq == 0)
+            {
+                changedUids = await remoteFolder
+                    .SearchAsync(BuildInitialSyncQuery(synchronizer), cancellationToken)
+                    .ConfigureAwait(false);
+            }
+            else
+            {
+                changedUids = await remoteFolder
+                    .SearchAsync(SearchQuery.ChangedSince(localHighestModSeq), cancellationToken)
+                    .ConfigureAwait(false);
+            }
 
             downloadedMessageIds = await DownloadMessagesByUidsAsync(client, remoteFolder, folder, changedUids, synchronizer, cancellationToken).ConfigureAwait(false);
 
@@ -308,25 +320,26 @@ public class UnifiedImapSynchronizer
             {
                 IList<UniqueId> changedUids;
 
-                if (client.Capabilities.HasFlag(ImapCapabilities.Sort))
+                if (isInitialSync)
                 {
                     changedUids = await remoteFolder
-                        .SortAsync(SearchQuery.ChangedSince(localHighestModSeq), [OrderBy.ReverseDate], cancellationToken)
+                        .SearchAsync(BuildInitialSyncQuery(synchronizer), cancellationToken)
                         .ConfigureAwait(false);
                 }
                 else
                 {
-                    changedUids = await remoteFolder
+                    if (client.Capabilities.HasFlag(ImapCapabilities.Sort))
-                        .SearchAsync(SearchQuery.ChangedSince(localHighestModSeq), cancellationToken)
+                    {
-                        .ConfigureAwait(false);
+                        changedUids = await remoteFolder
-                }
+                            .SortAsync(SearchQuery.ChangedSince(localHighestModSeq), [OrderBy.ReverseDate], cancellationToken)
-
+                            .ConfigureAwait(false);
-                if (isInitialSync)
+                    }
-                {
+                    else
-                    changedUids = changedUids
+                    {
-                        .OrderByDescending(a => a.Id)
+                        changedUids = await remoteFolder
-                        .Take((int)synchronizer.InitialMessageDownloadCountPerFolder)
+                            .SearchAsync(SearchQuery.ChangedSince(localHighestModSeq), cancellationToken)
-                        .ToList();
+                            .ConfigureAwait(false);
+                    }
                 }
 
                 downloadedMessageIds = await DownloadMessagesByUidsAsync(client, remoteFolder, folder, changedUids, synchronizer, cancellationToken).ConfigureAwait(false);
@@ -367,15 +380,12 @@ public class UnifiedImapSynchronizer
 
             if (folder.HighestKnownUid == 0)
             {
-                var remoteUids = await remoteFolder.SearchAsync(SearchQuery.All, cancellationToken).ConfigureAwait(false);
+                var initialUids = await remoteFolder
-
+                    .SearchAsync(BuildInitialSyncQuery(synchronizer), cancellationToken)
-                var initialUids = remoteUids
+                    .ConfigureAwait(false);
-                    .OrderByDescending(a => a.Id)
-                    .Take((int)synchronizer.InitialMessageDownloadCountPerFolder)
-                    .ToList();
 
                 downloadedMessageIds = await DownloadMessagesByUidsAsync(client, remoteFolder, folder, initialUids, synchronizer, cancellationToken).ConfigureAwait(false);
-                UpdateHighestKnownUid(folder, remoteFolder, remoteUids.Select(a => a.Id));
+                UpdateHighestKnownUid(folder, remoteFolder, initialUids.Select(a => a.Id));
             }
             else
             {
@@ -410,6 +420,22 @@ public class UnifiedImapSynchronizer
 
     #region Shared Helpers
 
+    private static SearchQuery BuildInitialSyncQuery(IImapSynchronizer synchronizer)
+    {
+        if (synchronizer is IBaseSynchronizer { Account: { } account })
+        {
+            var referenceDateUtc = account.CreatedAt ?? DateTime.UtcNow;
+            var cutoffDateUtc = account.InitialSynchronizationRange.ToCutoffDateUtc(referenceDateUtc);
+
+            if (cutoffDateUtc.HasValue)
+            {
+                return SearchQuery.DeliveredAfter(cutoffDateUtc.Value.ToUniversalTime().Date);
+            }
+        }
+
+        return SearchQuery.All;
+    }
+
     private async Task EnsureUidValidityStateAsync(MailItemFolder folder, IMailFolder remoteFolder)
     {
         if (folder.UidValidity != 0 && remoteFolder.UidValidity != folder.UidValidity)

Wino.Core/Synchronizers/OutlookSynchronizer.cs

@@ -55,14 +55,14 @@ public partial class OutlookSynchronizerJsonContext : JsonSerializerContext;
 /// 
 /// SYNCHRONIZATION STRATEGY:
 /// - Uses delta API for both initial and incremental sync
-/// - Initial sync: Downloads last 30 days of emails with metadata only
+/// - Initial sync: Downloads messages using the account's configured cutoff date with metadata only
 /// - Incremental sync: Uses delta token to get only changes since last sync
 /// - Messages are downloaded with metadata only (no MIME content during sync)
 /// - MIME files are downloaded on-demand when user explicitly reads a message
 /// 
 /// Key implementation details:
 /// - SynchronizeFolderAsync: Main entry point for per-folder synchronization
-/// - DownloadMailsForInitialSyncAsync: Downloads last 30 days using delta API with filter
+/// - DownloadMailsForInitialSyncAsync: Downloads messages using delta API with an optional cutoff filter
 /// - ProcessDeltaChangesAsync: Processes incremental changes using delta token
 /// - DownloadMessageMetadataBatchAsync: Downloads metadata in batches using Graph batch API
 /// - CreateMailCopyFromMessageAsync: Creates MailCopy from Message metadata
@@ -343,9 +343,9 @@ public class OutlookSynchronizer : WinoSynchronizer<RequestInformation, Message,
         // Check if we have a delta token
         if (string.IsNullOrEmpty(folder.DeltaToken))
         {
-            _logger.Debug("No delta token for folder {FolderName}. Starting initial sync (last 30 days).", folder.FolderName);
+            _logger.Debug("No delta token for folder {FolderName}. Starting initial sync.", folder.FolderName);
 
-            // Download mails for initial sync (last 30 days)
+            // Download mails for initial sync using the account's configured cutoff date.
             await DownloadMailsForInitialSyncAsync(folder, downloadedMessageIds, cancellationToken).ConfigureAwait(false);
         }
         else
@@ -367,27 +367,37 @@ public class OutlookSynchronizer : WinoSynchronizer<RequestInformation, Message,
     }
 
     /// <summary>
-    /// Downloads mails for initial synchronization using Delta API with 30-day filter.
+    /// Downloads mails for initial synchronization using Delta API with the account's configured cutoff date.
-    /// Downloads metadata only (no MIME content) for messages received in the last 30 days.
+    /// Downloads metadata only (no MIME content) for messages received after that date.
     /// </summary>
     private async Task DownloadMailsForInitialSyncAsync(MailItemFolder folder, List<string> downloadedMessageIds, CancellationToken cancellationToken)
     {
-        _logger.Debug("Starting initial mail download for folder {FolderName} (last 6 months)", folder.FolderName);
+        _logger.Debug("Starting initial mail download for folder {FolderName}", folder.FolderName);
 
         try
         {
-            // Calculate date 6 months ago
+            var referenceDateUtc = Account.CreatedAt ?? DateTime.UtcNow;
-            var sixMonthsAgo = DateTime.UtcNow.AddMonths(-6);
+            var initialSynchronizationCutoffDateUtc = Account.InitialSynchronizationRange.ToCutoffDateUtc(referenceDateUtc);
-            var filterDate = sixMonthsAgo.ToString("yyyy-MM-ddTHH:mm:ssZ");
+            var filterDate = initialSynchronizationCutoffDateUtc?.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ssZ");
 
-            _logger.Information("Downloading messages received after {FilterDate} for folder {FolderName}", filterDate, folder.FolderName);
+            if (filterDate != null)
+            {
+                _logger.Information("Downloading messages received after {FilterDate} for folder {FolderName}", filterDate, folder.FolderName);
+            }
+            else
+            {
+                _logger.Information("Downloading all available messages for folder {FolderName}", folder.FolderName);
+            }
 
-            // Use Delta API with receivedDateTime filter for last 6 months
             var messageCollectionPage = await _graphClient.Me.MailFolders[folder.RemoteFolderId].Messages.Delta.GetAsDeltaGetResponseAsync((config) =>
             {
                 config.QueryParameters.Select = outlookMessageSelectParameters;
                 config.QueryParameters.Orderby = ["receivedDateTime desc"];
-                config.QueryParameters.Filter = $"receivedDateTime ge {filterDate}";
+
+                if (filterDate != null)
+                {
+                    config.QueryParameters.Filter = $"receivedDateTime ge {filterDate}";
+                }
             }, cancellationToken).ConfigureAwait(false);
 
             var totalProcessed = 0;

Wino.Mail.ViewModels/AccountDetailsPageViewModel.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.ComponentModel;
+using System.Globalization;
 using System.Linq;
 using System.Threading.Tasks;
 using CommunityToolkit.Mvvm.ComponentModel;
@@ -12,6 +13,7 @@ using Wino.Core.Domain.Entities.Calendar;
 using Wino.Core.Domain;
 using Wino.Core.Domain.Entities.Shared;
 using Wino.Core.Domain.Enums;
+using Wino.Core.Domain.Extensions;
 using Wino.Core.Domain.Interfaces;
 using Wino.Core.Domain.Models.Accounts;
 using Wino.Core.Domain.Models.Folders;
@@ -101,6 +103,14 @@ public partial class AccountDetailsPageViewModel : MailBaseViewModel
         ? $"ms-appx:///Assets/Providers/{Account.SpecialImapProvider}.png"
         : $"ms-appx:///Assets/Providers/{Account?.ProviderType}.png";
     public string Address => Account?.Address ?? string.Empty;
+    public bool IsInitialSynchronizationSummaryVisible => Account?.CreatedAt.HasValue == true && Account.InitialSynchronizationRange != InitialSynchronizationRange.Everything;
+    public string InitialSynchronizationSummary => Account?.CreatedAt is not DateTime createdAtUtc
+        ? string.Empty
+        : Account.InitialSynchronizationRange.ToCutoffDateUtc(createdAtUtc) is not DateTime cutoffDateUtc
+            ? string.Empty
+            : string.Format(
+            Translator.AccountDetailsPage_InitialSynchronization_Description,
+            cutoffDateUtc.ToLocalTime().ToString("D", CultureInfo.CurrentUICulture));
 
     public List<ImapAuthenticationMethodModel> AvailableAuthenticationMethods { get; } =
     [
@@ -363,6 +373,8 @@ public partial class AccountDetailsPageViewModel : MailBaseViewModel
         OnPropertyChanged(nameof(IsFocusedInboxSupportedForAccount));
         OnPropertyChanged(nameof(ProviderIconPath));
         OnPropertyChanged(nameof(Address));
+        OnPropertyChanged(nameof(IsInitialSynchronizationSummaryVisible));
+        OnPropertyChanged(nameof(InitialSynchronizationSummary));
     }
 
     protected override async void OnPropertyChanged(PropertyChangedEventArgs e)

Wino.Mail.ViewModels/AccountSetupProgressPageViewModel.cs

@@ -170,6 +170,7 @@ public partial class AccountSetupProgressPageViewModel : MailBaseViewModel
         try
         {
             CustomServerInformation customServerInformation = null;
+            var accountCreatedAt = DateTime.UtcNow;
 
             // Build account in memory
             _createdAccount = new MailAccount
@@ -179,6 +180,8 @@ public partial class AccountSetupProgressPageViewModel : MailBaseViewModel
                 Name = WizardContext.AccountName,
                 SpecialImapProvider = WizardContext.SelectedProvider.SpecialImapProvider,
                 AccountColorHex = WizardContext.AccountColorHex,
+                CreatedAt = accountCreatedAt,
+                InitialSynchronizationRange = WizardContext.SelectedInitialSynchronizationRange,
                 IsCalendarAccessGranted = true
             };
 

Wino.Mail.ViewModels/Data/WelcomeWizardContext.cs

@@ -18,6 +18,9 @@ public partial class WelcomeWizardContext : ObservableObject
     [ObservableProperty]
     public partial string AccountColorHex { get; set; }
 
+    [ObservableProperty]
+    public partial InitialSynchronizationRange SelectedInitialSynchronizationRange { get; set; } = InitialSynchronizationRange.SixMonths;
+
     // Special IMAP fields (iCloud/Yahoo)
     [ObservableProperty]
     public partial string DisplayName { get; set; }
@@ -62,7 +65,8 @@ public partial class WelcomeWizardContext : ObservableObject
             SelectedProvider.Type,
             AccountName,
             BuildSpecialImapProviderDetails(),
-            AccountColorHex);
+            AccountColorHex,
+            SelectedInitialSynchronizationRange);
     }
 
     public void Reset()
@@ -70,6 +74,7 @@ public partial class WelcomeWizardContext : ObservableObject
         SelectedProvider = null;
         AccountName = null;
         AccountColorHex = null;
+        SelectedInitialSynchronizationRange = InitialSynchronizationRange.SixMonths;
         DisplayName = null;
         EmailAddress = null;
         AppSpecificPassword = null;

Wino.Mail.ViewModels/ImapCalDavSettingsPageViewModel.cs

@@ -997,7 +997,12 @@ public partial class ImapCalDavSettingsPageViewModel : MailBaseViewModel
                 SpecialImapProvider = _editingSpecialImapProvider,
                 IsCalendarAccessGranted = mode != ImapCalendarSupportMode.Disabled
             },
-            new AccountCreationDialogResult(MailProviderType.IMAP4, DisplayName.Trim(), providerDetails, string.Empty));
+            new AccountCreationDialogResult(
+                MailProviderType.IMAP4,
+                DisplayName.Trim(),
+                providerDetails,
+                string.Empty,
+                _wizardContext.SelectedInitialSynchronizationRange));
 
         if (serverInformation == null)
             return false;

Wino.Mail.ViewModels/ProviderSelectionPageViewModel.cs

@@ -6,6 +6,7 @@ using CommunityToolkit.Mvvm.Messaging;
 using Wino.Core.Domain;
 using Wino.Core.Domain.Enums;
 using Wino.Core.Domain.Interfaces;
+using Wino.Core.Domain.Models.Accounts;
 using Wino.Core.Domain.Models.Navigation;
 using Wino.Core.ViewModels.Data;
 using Wino.Mail.ViewModels.Data;
@@ -22,13 +23,26 @@ public partial class ProviderSelectionPageViewModel : MailBaseViewModel
 
     public List<IProviderDetail> Providers { get; private set; } = [];
     public List<AppColorViewModel> AvailableColors { get; private set; } = [];
+    public List<InitialSynchronizationRangeOption> InitialSynchronizationRanges { get; } =
+    [
+        new(InitialSynchronizationRange.ThreeMonths, Translator.AccountCreation_InitialSynchronization_3Months),
+        new(InitialSynchronizationRange.SixMonths, Translator.AccountCreation_InitialSynchronization_6Months),
+        new(InitialSynchronizationRange.NineMonths, Translator.AccountCreation_InitialSynchronization_9Months),
+        new(InitialSynchronizationRange.OneYear, Translator.AccountCreation_InitialSynchronization_Year),
+        new(InitialSynchronizationRange.Everything, Translator.AccountCreation_InitialSynchronization_Everything)
+    ];
 
     [ObservableProperty]
     public partial IProviderDetail SelectedProvider { get; set; }
 
     [ObservableProperty]
+    [NotifyPropertyChangedFor(nameof(IsColorSelected))]
     public partial AppColorViewModel SelectedColor { get; set; }
 
+    [ObservableProperty]
+    [NotifyPropertyChangedFor(nameof(IsInitialSynchronizationWarningVisible))]
+    public partial InitialSynchronizationRangeOption SelectedInitialSynchronizationRange { get; set; }
+
     [ObservableProperty]
     public partial string AccountName { get; set; }
 
@@ -36,6 +50,7 @@ public partial class ProviderSelectionPageViewModel : MailBaseViewModel
     public partial bool CanProceed { get; set; }
 
     public bool IsColorSelected => SelectedColor != null;
+    public bool IsInitialSynchronizationWarningVisible => SelectedInitialSynchronizationRange?.IsEverything == true;
 
     public ProviderSelectionPageViewModel(
         IProviderService providerService,
@@ -45,6 +60,7 @@ public partial class ProviderSelectionPageViewModel : MailBaseViewModel
         _providerService = providerService;
         _themeService = themeService;
         WizardContext = wizardContext;
+        SelectedInitialSynchronizationRange = InitialSynchronizationRanges.First(option => option.Range == InitialSynchronizationRange.SixMonths);
     }
 
     public override void OnNavigatedTo(NavigationMode mode, object parameters)
@@ -56,6 +72,10 @@ public partial class ProviderSelectionPageViewModel : MailBaseViewModel
             .Select(hex => new AppColorViewModel(hex))
             .ToList();
 
+        SelectedInitialSynchronizationRange = InitialSynchronizationRanges
+            .FirstOrDefault(option => option.Range == WizardContext.SelectedInitialSynchronizationRange)
+            ?? InitialSynchronizationRanges.First(option => option.Range == InitialSynchronizationRange.SixMonths);
+
         // Restore from wizard context if navigating back
         if (WizardContext.SelectedProvider != null)
         {
@@ -71,9 +91,12 @@ public partial class ProviderSelectionPageViewModel : MailBaseViewModel
         Validate();
     }
 
-    partial void OnSelectedProviderChanged(IProviderDetail value) => Validate();
+    partial void OnSelectedProviderChanged(IProviderDetail value)
+    {
+        Validate();
+    }
+
     partial void OnAccountNameChanged(string value) => Validate();
-    partial void OnSelectedColorChanged(AppColorViewModel value) => OnPropertyChanged(nameof(IsColorSelected));
 
     [RelayCommand]
     private void ClearColor() => SelectedColor = null;
@@ -92,6 +115,7 @@ public partial class ProviderSelectionPageViewModel : MailBaseViewModel
         WizardContext.SelectedProvider = SelectedProvider;
         WizardContext.AccountName = AccountName?.Trim();
         WizardContext.AccountColorHex = SelectedColor?.Hex ?? string.Empty;
+        WizardContext.SelectedInitialSynchronizationRange = SelectedInitialSynchronizationRange?.Range ?? InitialSynchronizationRange.SixMonths;
 
         if (WizardContext.IsGenericImap)
         {

Wino.Mail.WinUI/Dialogs/NewAccountDialog.xaml

@@ -55,6 +55,7 @@
     <Grid MinWidth="400" RowSpacing="12">
         <Grid Visibility="{x:Bind IsProviderSelectionVisible, Mode=OneWay}">
             <Grid.RowDefinitions>
+                <RowDefinition Height="Auto" />
                 <RowDefinition Height="Auto" />
                 <RowDefinition Height="*" />
             </Grid.RowDefinitions>
@@ -96,6 +97,48 @@
 
             </Grid>
 
+            <Border
+                x:Name="InitialSynchronizationPanel"
+                Grid.Row="1"
+                Margin="0,12,0,0"
+                Padding="12"
+                Background="{ThemeResource CardBackgroundFillColorDefaultBrush}"
+                BorderBrush="{ThemeResource CardStrokeColorDefaultBrush}"
+                BorderThickness="1"
+                CornerRadius="8"
+                Visibility="Collapsed">
+                <StackPanel Spacing="10">
+                    <StackPanel Spacing="2">
+                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.AccountCreation_InitialSynchronization_Title}" />
+                        <TextBlock
+                            Foreground="{ThemeResource TextFillColorSecondaryBrush}"
+                            Style="{StaticResource CaptionTextBlockStyle}"
+                            Text="{x:Bind domain:Translator.AccountCreation_InitialSynchronization_Description}"
+                            TextWrapping="WrapWholeWords" />
+                    </StackPanel>
+
+                    <ComboBox
+                        x:Name="InitialSynchronizationComboBox"
+                        HorizontalAlignment="Stretch"
+                        ItemsSource="{x:Bind InitialSynchronizationRanges, Mode=OneWay}"
+                        SelectionChanged="InitialSynchronizationSelectionChanged">
+                        <ComboBox.ItemTemplate>
+                            <DataTemplate x:DataType="accounts:InitialSynchronizationRangeOption">
+                                <TextBlock Text="{x:Bind DisplayText}" />
+                            </DataTemplate>
+                        </ComboBox.ItemTemplate>
+                    </ComboBox>
+
+                    <muxc:InfoBar
+                        x:Name="InitialSynchronizationWarningBar"
+                        IsOpen="True"
+                        Message="{x:Bind domain:Translator.AccountCreation_InitialSynchronization_EverythingWarning}"
+                        Severity="Warning"
+                        Title="{x:Bind domain:Translator.GeneralTitle_Warning}"
+                        Visibility="Collapsed" />
+                </StackPanel>
+            </Border>
+
 
             <ListView
                 Grid.Row="2"

Wino.Mail.WinUI/Dialogs/NewAccountDialog.xaml.cs

@@ -15,7 +15,7 @@ namespace Wino.Mail.WinUI.Dialogs;
 
 public sealed partial class NewAccountDialog : ContentDialog
 {
-    private readonly Dictionary<SpecialImapProvider, string> helpingLinks = new Dictionary<SpecialImapProvider, string>()
+    private readonly Dictionary<SpecialImapProvider, string> helpingLinks = new()
     {
         { SpecialImapProvider.iCloud, "https://support.apple.com/en-us/102654" },
         { SpecialImapProvider.Yahoo, "http://help.yahoo.com/kb/SLN15241.html" },
@@ -27,7 +27,6 @@ public sealed partial class NewAccountDialog : ContentDialog
     public static readonly DependencyProperty SelectedColorProperty = DependencyProperty.Register(nameof(SelectedColor), typeof(AppColorViewModel), typeof(NewAccountDialog), new PropertyMetadata(null, new PropertyChangedCallback(OnSelectedColorChanged)));
     public static readonly DependencyProperty SelectedCalendarModeIndexProperty = DependencyProperty.Register(nameof(SelectedCalendarModeIndex), typeof(int), typeof(NewAccountDialog), new PropertyMetadata(0));
 
-
     public AppColorViewModel? SelectedColor
     {
         get { return (AppColorViewModel?)GetValue(SelectedColorProperty); }
@@ -49,7 +48,6 @@ public sealed partial class NewAccountDialog : ContentDialog
         set { SetValue(SelectedMailProviderProperty, value); }
     }
 
-
     public bool IsProviderSelectionVisible
     {
         get { return (bool)GetValue(IsProviderSelectionVisibleProperty); }
@@ -63,10 +61,16 @@ public sealed partial class NewAccountDialog : ContentDialog
     }
 
     // List of available mail providers for now.
-
     public List<IProviderDetail> Providers { get; set; } = [];
-
     public List<AppColorViewModel> AvailableColors { get; set; } = [];
+    public List<InitialSynchronizationRangeOption> InitialSynchronizationRanges { get; } =
+    [
+        new(InitialSynchronizationRange.ThreeMonths, Translator.AccountCreation_InitialSynchronization_3Months),
+        new(InitialSynchronizationRange.SixMonths, Translator.AccountCreation_InitialSynchronization_6Months),
+        new(InitialSynchronizationRange.NineMonths, Translator.AccountCreation_InitialSynchronization_9Months),
+        new(InitialSynchronizationRange.OneYear, Translator.AccountCreation_InitialSynchronization_Year),
+        new(InitialSynchronizationRange.Everything, Translator.AccountCreation_InitialSynchronization_Everything)
+    ];
     public List<string> CalendarModeOptions { get; } =
     [
         Translator.ImapCalDavSettingsPage_CalendarModeCalDav,
@@ -74,7 +78,6 @@ public sealed partial class NewAccountDialog : ContentDialog
         Translator.ImapCalDavSettingsPage_CalendarModeDisabled
     ];
 
-
     public AccountCreationDialogResult? Result = null;
 
     public NewAccountDialog()
@@ -85,6 +88,8 @@ public sealed partial class NewAccountDialog : ContentDialog
         AvailableColors = themeService.Select(a => new AppColorViewModel(a)).ToList();
 
         UpdateSelectedColor();
+        InitialSynchronizationComboBox.SelectedItem = InitialSynchronizationRanges.First(option => option.Range == InitialSynchronizationRange.SixMonths);
+        UpdateInitialSynchronizationState();
     }
 
     private static void OnSelectedProviderChanged(DependencyObject obj, DependencyPropertyChangedEventArgs args)
@@ -105,6 +110,19 @@ public sealed partial class NewAccountDialog : ContentDialog
         SelectedColorEllipse.Fill = SelectedColor == null ? null : XamlHelpers.GetSolidColorBrushFromHex(SelectedColor.Hex);
     }
 
+    private void UpdateInitialSynchronizationState()
+    {
+        InitialSynchronizationPanel.Visibility = SelectedMailProvider == null ? Visibility.Collapsed : Visibility.Visible;
+        var selectedOption = InitialSynchronizationComboBox.SelectedItem as InitialSynchronizationRangeOption;
+        InitialSynchronizationWarningBar.Visibility = selectedOption?.IsEverything == true ? Visibility.Visible : Visibility.Collapsed;
+    }
+
+    private InitialSynchronizationRange GetInitialSynchronizationRange()
+    {
+        var selectedRange = (InitialSynchronizationComboBox.SelectedItem as InitialSynchronizationRangeOption)?.Range
+            ?? InitialSynchronizationRange.SixMonths;
+        return selectedRange;
+    }
 
     private void CancelClicked(ContentDialog sender, ContentDialogButtonClickEventArgs args)
     {
@@ -116,9 +134,11 @@ public sealed partial class NewAccountDialog : ContentDialog
         if (SelectedMailProvider == null)
             return;
 
+        var initialSynchronizationRange = GetInitialSynchronizationRange();
+
         if (IsSpecialImapServerPartVisible)
         {
-            // Special imap detail input.
+            // Special IMAP detail input.
             var calendarSupportMode = SelectedCalendarModeIndex switch
             {
                 1 => ImapCalendarSupportMode.LocalOnly,
@@ -132,7 +152,12 @@ public sealed partial class NewAccountDialog : ContentDialog
                 DisplayNameTextBox.Text.Trim(),
                 SelectedMailProvider.SpecialImapProvider,
                 calendarSupportMode);
-            Result = new AccountCreationDialogResult(SelectedMailProvider.Type, AccountNameTextbox.Text.Trim(), details, SelectedColor?.Hex ?? string.Empty);
+            Result = new AccountCreationDialogResult(
+                SelectedMailProvider.Type,
+                AccountNameTextbox.Text.Trim(),
+                details,
+                SelectedColor?.Hex ?? string.Empty,
+                initialSynchronizationRange);
             Hide();
 
             return;
@@ -140,11 +165,11 @@ public sealed partial class NewAccountDialog : ContentDialog
 
         Validate();
 
-        if (IsSecondaryButtonEnabled)
+        if (IsPrimaryButtonEnabled)
         {
             if (SelectedMailProvider.SpecialImapProvider != SpecialImapProvider.None)
             {
-                // This step requires app-sepcific password login for some providers.
+                // This step requires app-specific password login for some providers.
                 args.Cancel = true;
 
                 IsProviderSelectionVisible = false;
@@ -154,7 +179,12 @@ public sealed partial class NewAccountDialog : ContentDialog
             }
             else
             {
-                Result = new AccountCreationDialogResult(SelectedMailProvider.Type, AccountNameTextbox.Text.Trim(), null, SelectedColor?.Hex ?? string.Empty);
+                Result = new AccountCreationDialogResult(
+                    SelectedMailProvider.Type,
+                    AccountNameTextbox.Text.Trim(),
+                    null,
+                    SelectedColor?.Hex ?? string.Empty,
+                    initialSynchronizationRange);
                 Hide();
             }
         }
@@ -167,6 +197,7 @@ public sealed partial class NewAccountDialog : ContentDialog
     {
         ValidateCreateButton();
         ValidateNames();
+        UpdateInitialSynchronizationState();
     }
 
     // Returns whether we can create account or not.
@@ -199,6 +230,9 @@ public sealed partial class NewAccountDialog : ContentDialog
 
     private void ImapPasswordChanged(object sender, RoutedEventArgs e) => Validate();
 
+    private void InitialSynchronizationSelectionChanged(object sender, SelectionChangedEventArgs e)
+        => UpdateInitialSynchronizationState();
+
     private async void AppSpecificHelpButtonClicked(object sender, RoutedEventArgs e)
     {
         if (SelectedMailProvider == null ||

Wino.Mail.WinUI/Views/Account/AccountDetailsPage.xaml

@@ -210,6 +210,13 @@
                         </TransitionCollection>
                     </StackPanel.ChildrenTransitions>
 
+                    <muxc:InfoBar
+                        IsOpen="True"
+                        Margin="0,0,0,8"
+                        Message="{x:Bind ViewModel.InitialSynchronizationSummary, Mode=OneWay}"
+                        Severity="Informational"
+                        Title="{x:Bind domain:Translator.AccountDetailsPage_InitialSynchronization_Title}"
+                        Visibility="{x:Bind ViewModel.IsInitialSynchronizationSummaryVisible, Mode=OneWay}" />
 
                     <controls:SettingsCard
                         Command="{x:Bind ViewModel.EditAliasesCommand}"

Wino.Mail.WinUI/Views/ProviderSelectionPage.xaml

@@ -10,15 +10,12 @@
     xmlns:helpers="using:Wino.Helpers"
     xmlns:interfaces="using:Wino.Core.Domain.Interfaces"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+    xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
     mc:Ignorable="d">
 
-    <ScrollViewer
+    <ScrollViewer HorizontalAlignment="Center" VerticalScrollBarVisibility="Auto">
-        HorizontalAlignment="Center"
-        VerticalAlignment="Center"
-        VerticalScrollBarVisibility="Auto">
         <StackPanel
-            MaxWidth="480"
+            Margin="0,12"
-            Margin="0,24,0,24"
             HorizontalAlignment="Stretch"
             Spacing="20">
 
@@ -76,6 +73,50 @@
                 </Button>
             </Grid>
 
+            <Border
+                MaxWidth="600"
+                Padding="12"
+                Background="{ThemeResource CardBackgroundFillColorDefaultBrush}"
+                BorderBrush="{ThemeResource CardStrokeColorDefaultBrush}"
+                BorderThickness="1"
+                CornerRadius="8">
+                <StackPanel Spacing="10">
+                    <StackPanel Spacing="2">
+                        <TextBlock FontWeight="SemiBold" Text="{x:Bind domain:Translator.AccountCreation_InitialSynchronization_Title}" />
+                        <TextBlock
+                            Foreground="{ThemeResource TextFillColorSecondaryBrush}"
+                            Style="{StaticResource CaptionTextBlockStyle}"
+                            Text="{x:Bind domain:Translator.AccountCreation_InitialSynchronization_Description}"
+                            TextWrapping="WrapWholeWords" />
+                    </StackPanel>
+
+                    <ListView
+                        HorizontalAlignment="Center"
+                        HorizontalContentAlignment="Stretch"
+                        ItemsSource="{x:Bind ViewModel.InitialSynchronizationRanges, Mode=OneWay}"
+                        SelectedItem="{x:Bind ViewModel.SelectedInitialSynchronizationRange, Mode=TwoWay}">
+                        <ListView.ItemsPanel>
+                            <ItemsPanelTemplate>
+                                <ItemsStackPanel Orientation="Horizontal" />
+                            </ItemsPanelTemplate>
+                        </ListView.ItemsPanel>
+                        <ListView.ItemTemplate>
+                            <DataTemplate x:DataType="accounts:InitialSynchronizationRangeOption">
+                                <TextBlock Text="{x:Bind DisplayText}" />
+                            </DataTemplate>
+                        </ListView.ItemTemplate>
+                    </ListView>
+
+                    <muxc:InfoBar
+                        Title="{x:Bind domain:Translator.GeneralTitle_Warning}"
+                        Margin="0,2,0,0"
+                        IsOpen="True"
+                        Message="{x:Bind domain:Translator.AccountCreation_InitialSynchronization_EverythingWarning}"
+                        Severity="Warning"
+                        Visibility="{x:Bind ViewModel.IsInitialSynchronizationWarningVisible, Mode=OneWay}" />
+                </StackPanel>
+            </Border>
+
             <!--  Provider List  -->
             <ItemsView
                 HorizontalContentAlignment="Stretch"

Wino.Services/AccountService.cs

@@ -590,6 +590,11 @@ public class AccountService : BaseDatabaseService, IAccountService
     {
         Guard.IsNotNull(account);
 
+        if (!account.CreatedAt.HasValue)
+        {
+            account.CreatedAt = DateTime.UtcNow;
+        }
+
         var accountCount = await Connection.Table<MailAccount>().CountAsync();
 
         // If there are no accounts before this one, set it as startup account.

Wino.Services/DatabaseService.cs

@@ -79,6 +79,22 @@ public class DatabaseService : IDatabaseService
     {
         await EnsureKeyboardShortcutSchemaAsync().ConfigureAwait(false);
 
+        var accountColumns = await Connection.GetTableInfoAsync(nameof(MailAccount)).ConfigureAwait(false);
+
+        if (!accountColumns.Any(c => c.Name == nameof(MailAccount.CreatedAt)))
+        {
+            await Connection
+                .ExecuteAsync($"ALTER TABLE {nameof(MailAccount)} ADD COLUMN {nameof(MailAccount.CreatedAt)} TEXT NULL")
+                .ConfigureAwait(false);
+        }
+
+        if (!accountColumns.Any(c => c.Name == nameof(MailAccount.InitialSynchronizationRange)))
+        {
+            await Connection
+                .ExecuteAsync($"ALTER TABLE {nameof(MailAccount)} ADD COLUMN {nameof(MailAccount.InitialSynchronizationRange)} INTEGER NOT NULL DEFAULT {(int)InitialSynchronizationRange.SixMonths}")
+                .ConfigureAwait(false);
+        }
+
         var folderColumns = await Connection.GetTableInfoAsync(nameof(MailItemFolder)).ConfigureAwait(false);
 
         if (!folderColumns.Any(c => c.Name == nameof(MailItemFolder.HighestKnownUid)))

Wino.Services/WinoAccountDataSyncService.cs

@@ -211,6 +211,8 @@ public sealed class WinoAccountDataSyncService : IWinoAccountDataSyncService
             SpecialImapProvider = (SpecialImapProvider)mailbox.SpecialImapProvider,
             AccountColorHex = mailbox.AccountColorHex?.Trim(),
             Base64ProfilePictureData = string.Empty,
+            CreatedAt = DateTime.UtcNow,
+            InitialSynchronizationRange = InitialSynchronizationRange.SixMonths,
             IsCalendarAccessGranted = mailbox.IsCalendarAccessGranted,
             SynchronizationDeltaIdentifier = string.Empty,
             CalendarSynchronizationDeltaIdentifier = string.Empty,