Computer will not stay switched off

I normally leave my machine on 24/7 But on the odd occassion when I do try to turn it off this is what happens. It powers down ok and turns off but any time between 10 seconds and 2 minutes later it just boots itself up again although its not a major problem for me I would like to find out what is causing it to do so. Has anyone else had this happen?
Jim.

 

See if this helps:

Windows XP Restarts Unexpectedly or Restarts When You Shut Down the Computer
http://support.microsoft.com/default.aspx?scid=kb;en-us;320299

 

Abraxas Thanks for your help, By unchecking the automatic restart the computer now stays off after shutting down.

 

You're welcome. But, if the restart flag was set, causing the computer to restart on shutdown, chances are it was experiencing an error during the process.

Look in your event viewer for more information.