diff --git a/Lib/pydoc.py b/Lib/pydoc.py
--- a/Lib/pydoc.py
+++ b/Lib/pydoc.py
@@ -2299,7 +2299,9 @@ def _url_handler(url, content_type="text
 
         with warnings.catch_warnings():
             warnings.filterwarnings('ignore') # ignore problems during import
-            ModuleScanner().run(callback, key)
+            def onerror(modname):
+                pass
+            ModuleScanner().run(callback, key, onerror=onerror)
 
         # format page
         def bltinlink(name):