diff --git a/Cmdline/Action/Repo.cs b/Cmdline/Action/Repo.cs
index 06ab6ccd62..6d11af4d5c 100644
--- a/Cmdline/Action/Repo.cs
+++ b/Cmdline/Action/Repo.cs
@@ -328,7 +328,7 @@ private int SetRepositoryPriority(RepoPriorityOptions options)
                 return Exit.BADOPT;
             }
             var manager = RegistryManager.Instance(MainClass.GetGameInstance(Manager), repoData);
-            if (options.priority < 0 || options.priority > manager.registry.Repositories.Count)
+            if (options.priority < 0 || options.priority >= manager.registry.Repositories.Count)
             {
                 User.RaiseMessage(Properties.Resources.RepoPriorityInvalid,
                     options.priority, manager.registry.Repositories.Count - 1);