diff --git a/src/ClaudeDo.Installer/Steps/StartServiceStep.cs b/src/ClaudeDo.Installer/Steps/StartServiceStep.cs
index 270c179..0b97ce7 100644
--- a/src/ClaudeDo.Installer/Steps/StartServiceStep.cs
+++ b/src/ClaudeDo.Installer/Steps/StartServiceStep.cs
@@ -12,11 +12,11 @@ public sealed class StartServiceStep : IInstallStep
     {
         progress.Report($"Starting {ServiceName}...");
 
-        var (exit, output) = await ProcessRunner.RunAsync("sc.exe", $"start {ServiceName}", null, progress, ct);
+        var (exit, _) = await ProcessRunner.RunAsync("sc.exe", $"start {ServiceName}", null, progress, ct);
         if (exit == 0) return StepResult.Ok();
 
-        // Exit 1056 = already running — that's fine too.
-        if (output.Contains("1056", StringComparison.OrdinalIgnoreCase))
+        // Exit 1056 = ERROR_SERVICE_ALREADY_RUNNING — that's fine too.
+        if (exit == 1056)
         {
             progress.Report("Service was already running.");
             return StepResult.Ok();