Originally posted by: shekondar
That tiny little magnet probably won't cause any problems.
But, it IS possible to screw up a hard drive with magnets (unlike what others here have said) - I know this from experience. I left a large (about 4" diameter) GPS antenna with a magnetic base in my laptop bag for a couple of weeks once, and the drive got F'ed up. Not enough to prevent the computer from booting, but it did corrupt some files (caused enough damage that I had to reinstall the OS). Plus I think the magnet also screwed up the CD-ROM drive - it wouldn't read any CDs correctly after that.
I find it far more likely that perhaps just having a heavy object in your laptop bag did it, everything got banged around, and possibly did some damage that way. How difficult was it to reinstall the OS? If an external magnetic force actually did somehow affect the platters, it would wipe the low-level servo info too, and the heads wouldn't be able to seek properly near that area of the media at all. I would be interesting in seeing what a low-level defect-sector graph looked like on that drive, if that were true or not. I have slightly wondered, what with how small laptop HDs, if it
were possible since the physical distance between the metal casing and the platters is smaller, that laptop HDs could be affected more by external magnetic fields than the average desktop HD, but ... I have this feeling that if it did, it would have caused you far more issues than you seem to have encountered.