Is immediately scan the system for viruses and malware... In safe mode.
You might also want to try using it in a cooler location. Laptops are very sensitive to heat, so there's a chance it might be shutting down in order to try and prevent permanent damage from the heat. You SHOULD get warnings about this sort of thing, but a lot of brand name companies like to switch off useful diagnostic stuff, like Dell's habit of leaving SMART (early warning system for disk failure) turned off on new systems.
I have a laptop that I have enjoyed for several years with little trouble. Lately it has taken to randomly shutting down, even when I'm in mid-keystroke. I can restart it immediately by pushing the power button twice, but it may stay on for 1 minute or for 5 minutes, but it will ultimately shut down. The shutdown is complete and immediate, no messages, the screen goes blank and the hard drive spools down in a second. I wonder, should I junk it and buy another or spend a minimum of $100 to have Best Buy or someone look at fixing it. It's an e-machine so there was not a lot of investment. It has a AMD processor, 512K RAM and a 40G hard drive. Help?

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