diff --git a/src/ClaudeDo.Localization/locales/de.json b/src/ClaudeDo.Localization/locales/de.json
index d40850a9..4d8d14eb 100644
--- a/src/ClaudeDo.Localization/locales/de.json
+++ b/src/ClaudeDo.Localization/locales/de.json
@@ -407,7 +407,10 @@
       "body": "ClaudeDo kann den Hintergrund-Worker nicht erreichen. Normalerweise wird er bei der Anmeldung automatisch gestartet. Du kannst ihn jetzt starten oder neu installieren, falls das Problem bestehen bleibt.",
       "dismiss": "Ausblenden",
       "rerunInstaller": "Installer erneut ausführen",
-      "startWorker": "Worker starten"
+      "startWorker": "Worker starten",
+      "workerNotFound": "Worker-Programm nicht gefunden. Installation prüfen.",
+      "installerNotFound": "Installer nicht gefunden. Installation prüfen.",
+      "startFailed": "Start fehlgeschlagen: {0}"
     },
     "listSettings": {
       "title": "LISTENEINSTELLUNGEN",
@@ -777,7 +780,7 @@
   },
   "vm": {
     "connection": { "online": "Online", "connecting": "Verbinden…", "offline": "Offline" },
-    "shell": { "restartingWorker": "Worker wird neu gestartet…", "unexpectedError": "Unerwarteter Fehler: {0}" },
+    "shell": { "unexpectedError": "Unerwarteter Fehler: {0}" },
     "mainWindow": { "closeConfirm": { "message": "{0} Mission-Control-Sitzung(en) laufen noch. Beim Beenden werden sie abgebrochen. Trotzdem schließen?" } },
     "agentStatus": { "idle": "Leerlauf", "queued": "In Warteschlange", "running": "Läuft", "review": "Prüfung", "children": "Wartet auf Teilaufgaben", "done": "Fertig", "failed": "Fehlgeschlagen", "cancelled": "Abgebrochen" },
     "taskStatus": { "idle": "Leerlauf", "queued": "In Warteschlange", "running": "Läuft", "waitingForReview": "Wartet auf Prüfung", "waitingForChildren": "Wartet auf Teilaufgaben", "done": "Fertig", "failed": "Fehlgeschlagen", "cancelled": "Abgebrochen", "parked": "Geparkt", "interactive": "Interaktiv", "waiting": "Wartet" },
diff --git a/src/ClaudeDo.Localization/locales/en.json b/src/ClaudeDo.Localization/locales/en.json
index 3c27cca8..f02214d4 100644
--- a/src/ClaudeDo.Localization/locales/en.json
+++ b/src/ClaudeDo.Localization/locales/en.json
@@ -407,7 +407,10 @@
       "body": "ClaudeDo can't reach the background worker. It is normally started automatically at logon. You can start it now, or reinstall if the problem persists.",
       "dismiss": "Dismiss",
       "rerunInstaller": "Rerun Installer",
-      "startWorker": "Start Worker"
+      "startWorker": "Start Worker",
+      "workerNotFound": "Worker executable not found. Check the installation.",
+      "installerNotFound": "Installer not found. Check the installation.",
+      "startFailed": "Start failed: {0}"
     },
     "listSettings": {
       "title": "LIST SETTINGS",
@@ -777,7 +780,7 @@
   },
   "vm": {
     "connection": { "online": "Online", "connecting": "Connecting…", "offline": "Offline" },
-    "shell": { "restartingWorker": "Restarting worker…", "unexpectedError": "Unexpected error: {0}" },
+    "shell": { "unexpectedError": "Unexpected error: {0}" },
     "mainWindow": { "closeConfirm": { "message": "{0} Mission Control session(s) are still running. Closing the app will end them. Close anyway?" } },
     "agentStatus": { "idle": "Idle", "queued": "Queued", "running": "Running", "review": "Review", "children": "Waiting for Subtasks", "done": "Done", "failed": "Failed", "cancelled": "Cancelled" },
     "taskStatus": { "idle": "Idle", "queued": "Queued", "running": "Running", "waitingForReview": "Waiting for Review", "waitingForChildren": "Waiting for Subtasks", "done": "Done", "failed": "Failed", "cancelled": "Cancelled", "parked": "Parked", "interactive": "Interactive", "waiting": "Waiting" },
diff --git a/src/ClaudeDo.Ui/Services/InstallArtifactLocator.cs b/src/ClaudeDo.Ui/Services/InstallArtifactLocator.cs
index 73d22a76..6a744001 100644
--- a/src/ClaudeDo.Ui/Services/InstallArtifactLocator.cs
+++ b/src/ClaudeDo.Ui/Services/InstallArtifactLocator.cs
@@ -1,9 +1,10 @@
 namespace ClaudeDo.Ui.Services;
 
-// Two named types because DI resolves them by type, not by key.
-public sealed class InstallerLocator() : InstallArtifactLocator("uninstaller", "ClaudeDo.Installer.exe");
+// Two named types because DI resolves them by type, not by key. Not sealed: tests subclass
+// these to fake Find() without touching the real filesystem/registry.
+public class InstallerLocator() : InstallArtifactLocator("uninstaller", "ClaudeDo.Installer.exe");
 
-public sealed class WorkerLocator() : InstallArtifactLocator("worker", "ClaudeDo.Worker.exe");
+public class WorkerLocator() : InstallArtifactLocator("worker", "ClaudeDo.Worker.exe");
 
 /// <summary>
 /// Locates an executable inside a ClaudeDo install: walk up from the running
@@ -14,7 +15,7 @@ public abstract class InstallArtifactLocator(string subdir, string exeName)
 {
     private const string InstallJson = "install.json";
 
-    public string? Find()
+    public virtual string? Find()
         => FindByWalkingUp(AppContext.BaseDirectory)
            ?? (OperatingSystem.IsWindows() ? FindByRegistry() : null);
 
diff --git a/src/ClaudeDo.Ui/ViewModels/IslandsShellViewModel.cs b/src/ClaudeDo.Ui/ViewModels/IslandsShellViewModel.cs
index 864e2a33..1ead9b8e 100644
--- a/src/ClaudeDo.Ui/ViewModels/IslandsShellViewModel.cs
+++ b/src/ClaudeDo.Ui/ViewModels/IslandsShellViewModel.cs
@@ -631,20 +631,25 @@ public sealed partial class IslandsShellViewModel : ViewModelBase, IDisposable
         await _updateCheck.CheckNowAsync(CancellationToken.None);
     }
 
-    [ObservableProperty] private string? _restartWorkerStatus;
+    // How long to wait after launching the new worker process before deciding it survived
+    // (e.g. a port conflict kills it almost immediately — see #292 for the worker-side fix).
+    private const int RestartSurvivalCheckMs = 2000;
+
+    // Test seam: overrides the real kill-and-relaunch body, so tests can assert the
+    // success/failure footer routing without spawning a real worker process.
+    internal Func<Task>? RestartWorkerOperation { get; set; }
 
     [RelayCommand]
     private async Task RestartWorkerAsync()
     {
-        RestartWorkerStatus = Loc.T("vm.shell.restartingWorker");
         try
         {
-            await Task.Run(RestartWorkerService);
-            await FlashRestartStatusAsync("Worker restarted.");
+            await (RestartWorkerOperation ?? (() => Task.Run(RestartWorkerService)))();
+            FlashFooterSuccess("Worker restarted.");
         }
         catch (Exception ex)
         {
-            await FlashRestartStatusAsync($"Restart failed: {ex.Message}");
+            FlashFooterError($"Restart failed: {ex.Message} — check the worker log.");
         }
     }
 
@@ -670,14 +675,10 @@ public sealed partial class IslandsShellViewModel : ViewModelBase, IDisposable
             catch { /* may have exited or be inaccessible */ }
             finally { p.Dispose(); }
         }
-        System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(exe) { UseShellExecute = true });
-    }
 
-    private async Task FlashRestartStatusAsync(string text)
-    {
-        RestartWorkerStatus = text;
-        await Task.Delay(3000);
-        if (RestartWorkerStatus == text) RestartWorkerStatus = null;
+        var started = System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(exe) { UseShellExecute = true });
+        if (started is not null && started.WaitForExit(RestartSurvivalCheckMs))
+            throw new InvalidOperationException($"worker process exited immediately (code {started.ExitCode})");
     }
 
     private bool _updatingClaudeCli;
diff --git a/src/ClaudeDo.Ui/ViewModels/Modals/WorkerConnectionModalViewModel.cs b/src/ClaudeDo.Ui/ViewModels/Modals/WorkerConnectionModalViewModel.cs
index 48e4b5f6..8dc9f545 100644
--- a/src/ClaudeDo.Ui/ViewModels/Modals/WorkerConnectionModalViewModel.cs
+++ b/src/ClaudeDo.Ui/ViewModels/Modals/WorkerConnectionModalViewModel.cs
@@ -1,7 +1,9 @@
 using System;
 using System.Diagnostics;
 using System.IO;
+using ClaudeDo.Ui.Localization;
 using ClaudeDo.Ui.Services;
+using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 
 namespace ClaudeDo.Ui.ViewModels.Modals;
@@ -11,6 +13,9 @@ public sealed partial class WorkerConnectionModalViewModel : ViewModelBase
     private readonly WorkerLocator _workerLocator;
     private readonly InstallerLocator _installerLocator;
 
+    // Test seam: real Process.Start by default, swappable to simulate a blocked/failed launch.
+    internal Action<ProcessStartInfo> ProcessStarter { get; set; } = psi => Process.Start(psi);
+
     public WorkerConnectionModalViewModel(WorkerLocator workerLocator, InstallerLocator installerLocator)
     {
         _workerLocator = workerLocator;
@@ -19,15 +24,29 @@ public sealed partial class WorkerConnectionModalViewModel : ViewModelBase
 
     public Action? CloseAction { get; set; }
 
+    [ObservableProperty] private string? _errorText;
+
     [RelayCommand] private void Close() => CloseAction?.Invoke();
 
     [RelayCommand]
     private void StartWorker()
     {
         var exe = _workerLocator.Find();
-        if (exe is null) return;
-        try { Process.Start(new ProcessStartInfo(exe) { UseShellExecute = true }); }
-        catch { /* nothing useful to show */ }
+        if (exe is null)
+        {
+            ErrorText = Loc.T("modals.workerConnection.workerNotFound");
+            return;
+        }
+        try
+        {
+            ProcessStarter(new ProcessStartInfo(exe) { UseShellExecute = true });
+        }
+        catch (Exception ex)
+        {
+            ErrorText = Loc.T("modals.workerConnection.startFailed", ex.Message);
+            return;
+        }
+        ErrorText = null;
         CloseAction?.Invoke();
     }
 
@@ -35,18 +54,26 @@ public sealed partial class WorkerConnectionModalViewModel : ViewModelBase
     private void RerunInstaller()
     {
         var path = _installerLocator.Find();
-        if (path is null) return;
+        if (path is null)
+        {
+            ErrorText = Loc.T("modals.workerConnection.installerNotFound");
+            return;
+        }
         try
         {
             // See IslandsShellViewModel.UpdateNow: an inherited CWD inside the install dir
             // makes the installer block its own app\ rename.
-            Process.Start(new ProcessStartInfo(path)
+            ProcessStarter(new ProcessStartInfo(path)
             {
                 UseShellExecute = true,
                 WorkingDirectory = Path.GetTempPath(),
             });
-            Environment.Exit(0);
         }
-        catch { /* nothing useful to show */ }
+        catch (Exception ex)
+        {
+            ErrorText = Loc.T("modals.workerConnection.startFailed", ex.Message);
+            return;
+        }
+        Environment.Exit(0);
     }
 }
diff --git a/src/ClaudeDo.Ui/Views/Modals/WorkerConnectionModalView.axaml b/src/ClaudeDo.Ui/Views/Modals/WorkerConnectionModalView.axaml
index c2cc24e2..c62fe4dc 100644
--- a/src/ClaudeDo.Ui/Views/Modals/WorkerConnectionModalView.axaml
+++ b/src/ClaudeDo.Ui/Views/Modals/WorkerConnectionModalView.axaml
@@ -16,10 +16,14 @@
   </Window.KeyBindings>
 
   <ctl:ModalShell Title="{loc:Tr modals.workerConnection.title}" CloseCommand="{Binding CloseCommand}">
-    <Grid RowDefinitions="*,Auto" Margin="20,16">
+    <Grid RowDefinitions="*,Auto,Auto" Margin="20,16">
       <TextBlock Grid.Row="0" Classes="meta" TextWrapping="Wrap"
                  Text="{loc:Tr modals.workerConnection.body}"/>
-      <StackPanel Grid.Row="1" Orientation="Horizontal" Spacing="8"
+      <TextBlock Grid.Row="1" TextWrapping="Wrap" Margin="0,8,0,0"
+                 Foreground="{DynamicResource StatusErrorBrush}"
+                 IsVisible="{Binding ErrorText, Converter={x:Static ObjectConverters.IsNotNull}}"
+                 Text="{Binding ErrorText}"/>
+      <StackPanel Grid.Row="2" Orientation="Horizontal" Spacing="8"
                   HorizontalAlignment="Right" Margin="0,16,0,0">
         <Button Classes="btn" Content="{loc:Tr modals.workerConnection.dismiss}" Command="{Binding CloseCommand}"/>
         <Button Classes="btn" Content="{loc:Tr modals.workerConnection.rerunInstaller}" Command="{Binding RerunInstallerCommand}"/>
diff --git a/tests/ClaudeDo.Ui.Tests/IslandsShellViewModelRestartWorkerTests.cs b/tests/ClaudeDo.Ui.Tests/IslandsShellViewModelRestartWorkerTests.cs
new file mode 100644
index 00000000..bd0bc5b2
--- /dev/null
+++ b/tests/ClaudeDo.Ui.Tests/IslandsShellViewModelRestartWorkerTests.cs
@@ -0,0 +1,41 @@
+using System;
+using System.Threading.Tasks;
+using ClaudeDo.Data.Models;
+using ClaudeDo.Ui.ViewModels;
+
+namespace ClaudeDo.Ui.Tests;
+
+// Covers the "restart worker" footer feedback fix: RestartWorkerStatus used to be set but was
+// never bound in any view, so a died-on-launch worker (e.g. a port conflict, see #292) restarted
+// silently. RestartWorkerOperation is a test seam standing in for the real kill-and-relaunch +
+// short-timeout survival check, so these tests only assert the success/failure routing to the
+// shared footer strip (WorkerLogText/WorkerLogLevel), not real process spawning.
+public class IslandsShellViewModelRestartWorkerTests
+{
+    [Fact]
+    public async Task ProcessSurvives_FlashesFooterSuccess()
+    {
+        var vm = new IslandsShellViewModel { RestartWorkerOperation = () => Task.CompletedTask };
+
+        await vm.RestartWorkerCommand.ExecuteAsync(null);
+
+        Assert.Equal(WorkerLogLevel.Success, vm.WorkerLogLevel);
+        Assert.Contains("restarted", vm.WorkerLogText);
+        Assert.True(vm.IsWorkerLogVisible);
+    }
+
+    [Fact]
+    public async Task ProcessDiesWithinTimeout_FlashesFooterError()
+    {
+        var vm = new IslandsShellViewModel
+        {
+            RestartWorkerOperation = () => throw new InvalidOperationException("worker process exited immediately (code 1)")
+        };
+
+        await vm.RestartWorkerCommand.ExecuteAsync(null);
+
+        Assert.Equal(WorkerLogLevel.Error, vm.WorkerLogLevel);
+        Assert.Contains("worker process exited immediately", vm.WorkerLogText);
+        Assert.True(vm.IsWorkerLogVisible);
+    }
+}
diff --git a/tests/ClaudeDo.Ui.Tests/ViewModels/WorkerConnectionModalViewModelTests.cs b/tests/ClaudeDo.Ui.Tests/ViewModels/WorkerConnectionModalViewModelTests.cs
new file mode 100644
index 00000000..229960a7
--- /dev/null
+++ b/tests/ClaudeDo.Ui.Tests/ViewModels/WorkerConnectionModalViewModelTests.cs
@@ -0,0 +1,85 @@
+using ClaudeDo.Ui.Services;
+using ClaudeDo.Ui.ViewModels.Modals;
+
+namespace ClaudeDo.Ui.Tests.ViewModels;
+
+public sealed class WorkerConnectionModalViewModelTests
+{
+    private sealed class FakeWorkerLocator(string? path) : WorkerLocator
+    {
+        public override string? Find() => path;
+    }
+
+    private sealed class FakeInstallerLocator(string? path) : InstallerLocator
+    {
+        public override string? Find() => path;
+    }
+
+    [Fact]
+    public void StartWorker_ExeNotFound_ShowsErrorAndKeepsDialogOpen()
+    {
+        var vm = new WorkerConnectionModalViewModel(new FakeWorkerLocator(null), new FakeInstallerLocator(null));
+        var closed = false;
+        vm.CloseAction = () => closed = true;
+
+        vm.StartWorkerCommand.Execute(null);
+
+        Assert.False(closed);
+        Assert.False(string.IsNullOrEmpty(vm.ErrorText));
+    }
+
+    [Fact]
+    public void StartWorker_ProcessStartThrows_ShowsErrorAndKeepsDialogOpen()
+    {
+        var vm = new WorkerConnectionModalViewModel(new FakeWorkerLocator(@"C:\fake\ClaudeDo.Worker.exe"), new FakeInstallerLocator(null))
+        {
+            ProcessStarter = _ => throw new InvalidOperationException("blocked by AV")
+        };
+        var closed = false;
+        vm.CloseAction = () => closed = true;
+
+        vm.StartWorkerCommand.Execute(null);
+
+        Assert.False(closed);
+        Assert.Contains("blocked by AV", vm.ErrorText);
+    }
+
+    [Fact]
+    public void StartWorker_Success_ClearsErrorAndClosesDialog()
+    {
+        var vm = new WorkerConnectionModalViewModel(new FakeWorkerLocator(@"C:\fake\ClaudeDo.Worker.exe"), new FakeInstallerLocator(null))
+        {
+            ProcessStarter = _ => { }
+        };
+        var closed = false;
+        vm.CloseAction = () => closed = true;
+
+        vm.StartWorkerCommand.Execute(null);
+
+        Assert.True(closed);
+        Assert.Null(vm.ErrorText);
+    }
+
+    [Fact]
+    public void RerunInstaller_NotFound_ShowsErrorAndDoesNotThrow()
+    {
+        var vm = new WorkerConnectionModalViewModel(new FakeWorkerLocator(null), new FakeInstallerLocator(null));
+
+        vm.RerunInstallerCommand.Execute(null);
+
+        Assert.False(string.IsNullOrEmpty(vm.ErrorText));
+    }
+
+    [Fact]
+    public void RerunInstaller_ProcessStartThrows_ShowsError()
+    {
+        var vm = new WorkerConnectionModalViewModel(new FakeWorkerLocator(null), new FakeInstallerLocator(@"C:\fake\ClaudeDo.Installer.exe"))
+        {
+            ProcessStarter = _ => throw new InvalidOperationException("blocked by AV")
+        };
+
+        vm.RerunInstallerCommand.Execute(null);
+
+        Assert.Contains("blocked by AV", vm.ErrorText);
+    }
+}