diff --git a/project.py b/project.py
index b80ad31..946a6ac 100644
--- a/project.py
+++ b/project.py
@@ -1516,7 +1516,7 @@
             except:
               return None
 
-          if e.code == 404:
+          if e.code in (401, 403, 404):
             keep = False
             return False
           elif _content_type() == 'text/plain':