Error encountered; please report this error to a wizard.

Error was: E_TYPE (Type mismatch); value: 0

VerbLoc:VerbProgrammerThisPlayerLine
#350:_render_delete #789#350#748714
#302:tell_www_page #789#350#748721
#80:serve_page #789#80#748742
#81:do_GET #55#7487#748712
#81:do_null_command #55#7487#74879
#80:do_null_command #789#80#74871

You can cut-and-paste the following:

#350:_render_delete (this == #350), line 14: Type mismatch
... called from #302:tell_www_page (this == #350), line 21
... called from #80:serve_page (this == #80), line 42
... called from #81:do_GET (this == #7487), line 12
... called from #81:do_null_command (this == #7487), line 9
... called from #80:do_null_command (this == #80), line 1
(end of traceback)