their is no file extension in \\domain\sysvol\policies\script

I was getting an error message during logon

"their is no file extension in \\domain\sysvol\policies\{GUID}\scripts\logon"

A logon script called by GPO was failing to run. I created a shortcut the script within sysvol and the shortcut also failed to launch the script with the same error message.
Calling the script from a Batch file worked ok.

The problem turned out to be the GPO was calling a VBS script with a long name. Renaming the VBS script to 8 characters or less resolved the issue.