diff --git a/video_metadata/views/file_listing.py b/video_metadata/views/file_listing.py
index df7b40f..d12f392 100644
--- a/video_metadata/views/file_listing.py
+++ b/video_metadata/views/file_listing.py
@@ -74,7 +74,9 @@ def getFolderJSON(subpath = ''):
 
     # validate input
     if re.search('\.\.', subpath) or not os.path.exists(full_path):
-        errors.append('invalid path?: {}'.format(full_path))
+        errors.append('invalid path: {}'.format(full_path))
+    elif not os.path.isdir(full_path):
+        errors.append('path is not a directory: {}'.format(full_path))
     else:
         for entry in os.scandir(full_path):
             # TODO: remove 'getPathInfo()' when finished with async file listing