REMOVE AND PREVENT ACCESS TO SHUTDOWN COMMAND

You can prevent and remove the shutdown command in xp by enabling it in group policy. To do so, follow the steps below

Start->Run->Type"gpedit.msc"

In the "user configuration" select Administrative templates->start menu and taskbar, in the right side of the screen you will find lots of options, in that select "Remove and prevent access to shutdown command". Double click it and select enable. Click ok.

There are lots of other options which you can enable there.

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AUTOMATIC SHUTDOWN

You can turnoff your computer automatically without using any softwares.
Follow the instructions carefully.

RIGHT CLICK->NEW->SHORTCUT->TYPE "shutdown.exe -s -t 3600" where 3600 is time in seconds.You can give any values in seconds.Double click to activate it.

Inorder to deactivate it follow the above steps but type "shutdown.exe -a" & double click to activate it.

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