Unable to shutdown my system

Hi all,

I'm running Windows XP on my Toshiba laptop and on many occasions, I
failed to shut down my system. After clicking "Shut Down" from the
menu, only a handful of processes are shutdown (as seen after pressing
Ctrl + Alt + Del). I have to manually shut it down by holding down on
the power button. I really hope you people who are well-versed in this
to help me resolve my problem.

Thanking you all in advance.

_JC

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