Windows XP Auto Shutdown

Is there any way through group policies to force machines shutdown everyday at a certain time?

I have experimented with using the following command line:
at 18:00 /every:ME,T,W,Th,F shutdown /l /y /c

However, the scheduled task above did not work, because of the system account.

I would like to implement auto shutdown via GPOs or scripts.

Any ideas?

Thanks





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