Here is a small bit of software called Auto Shutdown Professional which can secure your computer when you are away.
With this software you get the freedom to perform an unassisted shutdown, restart, logoff, standby, hibernate or you can even lock your PC based on the time of day, inactivity or battery power level. The Pro version features a system service module that can work with Windows 2000 and XP when a user is not logged in. AutoShutdown can also clean up files when it performs an action – wiping any trace from your recycle bin, temporary files, recent documents, cookies or other files.
AutoShutdown can perform events at a scheduled date and time, after a period of inactivity or according to your convenience.For example,you can set it to shut down every day at 8:00 am in the morning .You can also instruct it to clean up your temporary files.history,cookies,cache etc before shutting down.
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