diff --git a/gsm-backend/services/serverUpdates.js b/gsm-backend/services/serverUpdates.js
index e2c3156..8c0947d 100644
--- a/gsm-backend/services/serverUpdates.js
+++ b/gsm-backend/services/serverUpdates.js
@@ -495,23 +495,28 @@ const updateHandlers = {
         `-v ${installHostDir}:/appdata/space-engineers/SpaceEngineersDedicated`,
         `-v ${steamHostDir}:/home/wine/.steam`,
         `mmmaxwwwell/space-engineers-dedicated-docker-linux:latest`,
-        `-c "runuser -l wine bash -c 'steamcmd +@sSteamCmdForcePlatformType windows +force_install_dir /appdata/space-engineers/SpaceEngineersDedicated +login anonymous +app_update ${appId} +quit'"`
+        `-c "runuser -l wine bash -c 'steamcmd +@sSteamCmdForcePlatformType windows +force_install_dir /appdata/space-engineers/SpaceEngineersDedicated +login anonymous +app_update ${appId} validate +quit'"`
       ].join(" ");
 
       const updateResult = await ssh.execCommand(updateCmd, { execOptions: { timeout: 1200000 } }); // 20 min
       console.log("[Update] SteamCMD output (tail):", updateResult.stdout.slice(-2000));
 
-      const out = updateResult.stdout || "";
-      const success = out.includes("Success! App '298740'") || out.includes("fully installed");
-      if (!success) {
-        const errLine = out.match(/Error![^\n]*/)?.[0] || updateResult.stderr || "Unbekannter Fehler";
-        throw new Error("Update fehlgeschlagen: " + errLine);
-      }
-
-      // New build id
+      // Verify success by re-reading appmanifest: buildid should now match TargetBuildID (or have changed)
       const newManifest = await ssh.execCommand(`cat ${manifestPath} 2>/dev/null`);
       const newMatch = (newManifest.stdout || "").match(/"buildid"\s*"([^"]+)"/);
+      const newTargetMatch = (newManifest.stdout || "").match(/"TargetBuildID"\s*"([^"]+)"/);
       const newBuildId = newMatch ? newMatch[1] : null;
+      const newTargetBuildId = newTargetMatch ? newTargetMatch[1] : null;
+
+      const stillPending = newTargetBuildId && newTargetBuildId !== "0" && newTargetBuildId !== newBuildId;
+      const buildChanged = oldBuildId && newBuildId && oldBuildId !== newBuildId;
+      const out = updateResult.stdout || "";
+      const reportedSuccess = out.includes("Success! App '298740'") || out.includes("fully installed");
+
+      if (!buildChanged && !reportedSuccess && stillPending) {
+        const errLine = out.match(/Error![^\n]*/)?.[0] || updateResult.stderr || "SteamCMD meldet noch ausstehendes Update";
+        throw new Error("Update fehlgeschlagen: " + errLine);
+      }
 
       return {
         success: true,