Logoff Script (/AUTO) for all users

I've added "c:\progra~1\ccleaner\ccleaner.exe" /AUTO to a batch file that is called as a logoff script each time a user logs off the computer. The problem is that it only works for the user that installed ccleaner, it does absolutely nothing for all other users. Any ideas on how to get it to work for all users as a logoff script ??

Thanks.