Fix the defects found by adversarial review of the .NET 8 migration

- MboxParser now normalizes line endings to CRLF when writing message
  bytes: the server's message pipeline requires CRLF, so an LF-only
  (Unix) mbox previously produced stored .eml files the server could
  not parse. Verified end to end: an LF-only mbox imports with correct
  subjects, senders, dates and bodies.
- ImportTool writes each message as {account}\XY\{GUID}.eml (the
  server's on-disk convention) so ImportMessageFromFileToIMAPFolder
  never relocates the file; previously a failure after the server's
  internal move orphaned the message at a path the cleanup could not
  see. Cleanup also no longer aborts the import on non-IO errors.
- ucWizard.ShowPage restores the pre-validation button states instead
  of force-enabling all three; force-enabling let a failed validation
  on the first page enable Previous, and clicking it crashed with
  ShowPage(-1). Latent for DBSetup (its first page never fails);
  ImportTool's first pages validate, making it reachable.
- ucMboxSelect skips mail-client index files (.msf/.dat) so a
  Thunderbird profile folder imports cleanly (Inbox.msf previously
  collided with the Inbox mbox and imported garbage).
- ImportTool refuses /silent - the shared wizard would otherwise
  auto-run all pages with empty selections.
- InstallDotNetRuntime checks the runtime bundle's exit code (0/3010 =
  success); Exec only reports launch failures, so a failed install
  previously passed silently and the DB tools then could not start.
  MinVersion raised to Windows 10 1607, the .NET 8 runtime's floor -
  on older Windows the runtime install fails and the server would be
  left without a database.
- build-tools.ps1 cleans each publish folder before publishing;
  dotnet publish never removes orphans, and the installer wildcards
  the folder's entire contents into {app}\Bin.

Findings produced by a five-lens adversarial review (12 raised, 9
confirmed after refutation passes, all fixed).

Author: chrisholloway5

build/build-tools.ps1

@@ -18,6 +18,10 @@ foreach ($project in $publishProjects) {
     $csproj = Join-Path $toolsDir "$project\$project.csproj"
     $output = Join-Path $toolsDir "$project\publish"
 
+    # Start from a clean folder: the installer wildcards its entire contents,
+    # and dotnet publish never removes files a previous publish left behind.
+    if (Test-Path $output) { Remove-Item -Recurse -Force $output }
+
     Write-Host "Publishing $project -> $output"
     dotnet publish $csproj -c $Configuration -o $output
     if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }

hmailserver/installation/hMailServerInnoExtension.iss

@@ -297,6 +297,17 @@ begin
 	begin
 		MsgBox('The .NET 8 Desktop Runtime could not be installed. The database setup tools will not work until it is installed.' + #13#10 +
 		       SysErrorMessage(ResultCode), mbError, MB_OK);
+		Exit;
+	end;
+
+	// Exec returns True whenever the process launched; the actual install
+	// result is the exit code. 0 = success, 3010 = success, reboot required.
+	if (ResultCode <> 0) and (ResultCode <> 3010) then
+	begin
+		MsgBox('The .NET 8 Desktop Runtime installation failed with exit code ' + IntToStr(ResultCode) + '.' + #13#10 +
+		       'The database setup tools will not work until the runtime is installed. ' +
+		       'Install it manually from https://dotnet.microsoft.com/download/dotnet/8.0 and then run ' +
+		       'DBSetupQuick.exe from the hMailServer Bin folder.', mbError, MB_OK);
 	end;
 end;
 

hmailserver/installation/section_setup.iss

@@ -12,8 +12,8 @@ AllowNoIcons=yes
 Uninstallable=true
 DirExistsWarning=no
 CreateAppDir=true
-; Windows 7 SP1. Inno Setup 6 refuses anything below 6.1, and the old Vista SP1
-; floor was fiction anyway: this is an x64-only build whose Control Panel and
-; setup tools need the .NET 8 Desktop Runtime (bundled, installed when
-; missing) and whose binaries link the VC++ v145 runtime.
-MinVersion=6.1sp1
+; Windows 10 1607 (build 14393): the floor of the .NET 8 Desktop Runtime,
+; which the Control Panel and the setup tools require (bundled, installed
+; when missing - its installer refuses anything older, which would leave the
+; server without a database). The binaries link the VC++ v145 runtime.
+MinVersion=10.0.14393

hmailserver/source/Tools/ImportTool/MboxImport/MboxParser.cs

@@ -14,8 +14,10 @@ namespace ImportTool.MboxImport
    /// the start of the file or directly after a blank line, which covers the
    /// classic mbox variants as well as Thunderbird's "From - <date>" form. Both
    /// LF and CRLF line endings are handled, the final message is emitted, and
-   /// mboxrd-style ">From " quoting is reversed. Message bytes are otherwise
-   /// preserved exactly; no dot-stuffing or trailing separators are added.
+   /// mboxrd-style ">From " quoting is reversed. Line endings are normalized
+   /// to CRLF - the server's message pipeline requires it - but message bytes
+   /// are otherwise preserved; no dot-stuffing or trailing separators are
+   /// added.
    /// </summary>
    internal static class MboxParser
    {
@@ -129,11 +131,31 @@ private static void WriteBodyLine(MemoryStream message, byte[] line)
 
          if (quoteCount > 0 && StartsWithFromMarkerAt(line, quoteCount))
          {
-            message.Write(line, 1, line.Length - 1);
+            WriteNormalizedLine(message, line, 1);
             return;
          }
 
-         message.Write(line, 0, line.Length);
+         WriteNormalizedLine(message, line, 0);
+      }
+
+      /// <summary>
+      /// Writes the line starting at <paramref name="offset"/>, rewriting a
+      /// bare LF terminator to CRLF.
+      /// </summary>
+      private static void WriteNormalizedLine(MemoryStream message, byte[] line, int offset)
+      {
+         int length = line.Length - offset;
+
+         if (length >= 1 && line[line.Length - 1] == '\n' &&
+             (length < 2 || line[line.Length - 2] != '\r'))
+         {
+            message.Write(line, offset, length - 1);
+            message.WriteByte((byte)'\r');
+            message.WriteByte((byte)'\n');
+            return;
+         }
+
+         message.Write(line, offset, length);
       }
 
       private static bool StartsWithFromMarkerAt(byte[] line, int offset)

hmailserver/source/Tools/ImportTool/MboxImport/ucMboxProgress.cs

@@ -115,7 +115,15 @@ private void RunImport()
 
       private bool ImportMessage(hMailServer.Utilities utilities, string destinationDirectory, string folderName, byte[] messageBytes)
       {
-         var fileName = Path.Combine(destinationDirectory, "{" + Guid.NewGuid().ToString().ToUpperInvariant() + "}.eml");
+         // Use the server's on-disk convention, {account}\XY\{GUID}.eml where
+         // XY is the GUID's first two characters. A file placed anywhere else
+         // is moved (and renamed) by the import, after which a failure would
+         // leave it orphaned at a path we no longer know.
+         var guid = Guid.NewGuid().ToString().ToUpperInvariant();
+         var subDirectory = Path.Combine(destinationDirectory, guid.Substring(0, 2));
+         Directory.CreateDirectory(subDirectory);
+
+         var fileName = Path.Combine(subDirectory, "{" + guid + "}.eml");
 
          File.WriteAllBytes(fileName, messageBytes);
 
@@ -129,12 +137,13 @@ private bool ImportMessage(hMailServer.Utilities utilities, string destinationDi
             AddToLog("A message failed to import: " + ex.Message);
          }
 
-         // The server did not take ownership of the file; do not leave it behind.
+         // The server did not take ownership of the file; do not leave it
+         // behind. Cleanup failure must not abort the remaining import.
          try
          {
             File.Delete(fileName);
          }
-         catch (IOException)
+         catch (Exception)
          {
          }
 

hmailserver/source/Tools/ImportTool/MboxImport/ucMboxSelect.cs

@@ -55,6 +55,13 @@ private void buttonSelectDirectory_Click(object sender, EventArgs e)
             listFiles.Items.Clear();
             foreach (var file in Directory.GetFiles(dialog.SelectedPath))
             {
+               // Skip mail-client index files that live next to the mboxes
+               // (e.g. Thunderbird's Inbox.msf next to Inbox).
+               var extension = Path.GetExtension(file);
+               if (string.Equals(extension, ".msf", StringComparison.OrdinalIgnoreCase) ||
+                   string.Equals(extension, ".dat", StringComparison.OrdinalIgnoreCase))
+                  continue;
+
                var item = listFiles.Items.Add(file);
                item.SubItems.Add(ucMboxProgress.GetFolderNameForFile(file));
             }

hmailserver/source/Tools/ImportTool/Program.cs

@@ -15,6 +15,15 @@ static void Main()
 
          CommandLineParser.Parse();
 
+         // The shared wizard auto-runs all pages when /silent is passed. The
+         // import wizards have no scripted-argument support, so a silent run
+         // could only fail (or import with empty selections); refuse it.
+         if (CommandLineParser.IsSilent())
+         {
+            MessageBox.Show("The hMailServer Import Tool does not support silent mode.", "hMailServer Import Tool");
+            return;
+         }
+
          hMailServer.Application application = new hMailServer.Application();
          if (!Authenticator.AuthenticateUser(application))
             return;

hmailserver/source/Tools/Shared/Wizard/ucWizard.cs

@@ -91,9 +91,13 @@ public bool ShowPage(int pageNo)
             }
             finally
             {
-               buttonNext.Enabled = true;
-               buttonPrevious.Enabled = true;
-               buttonCancel.Enabled = true;
+               // Restore the states from before OnLeavePage; enabling all
+               // three unconditionally would enable Previous on the first
+               // page after a failed validation, and clicking it would call
+               // ShowPage(-1).
+               buttonNext.Enabled = nextEnabled;
+               buttonPrevious.Enabled = previousEnabled;
+               buttonCancel.Enabled = cancelEnabled;
             }
          }