Some machines just get an infection or a damaged OS and this happens.
Try this. Boot a live CD. Here's how -> http://www.howtogeek.com/howto/windows-vista/use-ubuntu-live-cd-to-backup-files-from-your-dead-windows-computer/
Scared of that? How about Hiren's Boot CD with it's mini-XP? http://www.hiren.info/pages/bootcd
Bob
purchased acer aspire laptop just paid it off from rental agency in september. one day out of the blue i get a black boot manger screen that just keeps looping. tech thought it was a virus at first, then said no, it's a motherboard problem and cant be repaired. I had 4 gigs of ram, dvd burner, 250 gig hard drive, mounds of music and pics, etc. Can't i just get a a new motherboard? im in school and homework is done online so im screwed. any suggestions would be greatly appreciated.

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