Hi, computers are incredibly complicated things, so there could be a number of answers to different potential problems. However, I assume that the computer is still making a noise, like a small fan going around. If not, it could be that the fan or fans has / have stopped working and the processor is overheating. All computers have a fail safe device which shuts the computer down before the heat builds up too much and 'fries' the main processor. The fans are inexpensive to buy, but not easy to fit, so it may be better to take it to a reputable local repairer to do the work. Its probably better to stay away from the national pc repairers as they, in my experience, do not seem to take as much care as the local guy generally does.
It is unlikely to be a virus which does this sort of thing as they generally want to take over your computer and use it in the background to send out lots of emails, which you then know nothing about. Or they want to access any information on the pc for their own personal gain, etc.
Please try the suggestion I have made but come back again if this does not work and I can try a couple of different things to keep it working. At that time I would appreciate a bit more information about the type of pc and speed of processor, operating system (os) and any programs you may be running.
Hope this helps
Regards
John Bates
December 2008
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