standby, turn off and reset bar problem

Hi. I hope you can help me. My friend got Dell desktop computer with windows
xp on it. Everything is working, but there is problem with turn off, standby
and reset bar. I hope you know what I mean, when you want to turn it off
there is a bar with these 3 functions. When you click turn it off it is
reseting itself. And standby and reset buttons are gray and I am not able to
use them at all. I found few suggestions on web, but I prefer to ask by
myself.
And I think power button on computer is reseting itself all the time, too.
So the only way to turn it off is just unplug it.
Thank you for your help.

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