diff --git a/lib/game.dart b/lib/game.dart
index eb28a58..154b19e 100644
--- a/lib/game.dart
+++ b/lib/game.dart
@@ -123,6 +123,8 @@ class GameServerPageState extends State<GameServerPage> {
                       manifest.add("${M.mod_id}");
                     }
 
+                    settings.assertModsFolderExists();
+
                     result =
                         await Process.run(settings.getSteamCmd(), manifest);