diff --git a/src/Runner.Worker/ActionManifestManager.cs b/src/Runner.Worker/ActionManifestManager.cs
index 7fb1f4f1b..759cd36ff 100644
--- a/src/Runner.Worker/ActionManifestManager.cs
+++ b/src/Runner.Worker/ActionManifestManager.cs
@@ -61,7 +61,7 @@ namespace GitHub.Runner.Worker
             // we can just remove the # of characters from the fileName according to the length of the basePath
             string basePath = HostContext.GetDirectory(WellKnownDirectory.Actions);
             string fileRelativePath = manifestFile;
-            if (manifestFile.Length > basePath.Length + 1)
+            if (manifestFile.Contains(basePath))
             {
                 fileRelativePath = manifestFile.Remove(0, basePath.Length + 1);
             }