I have Windows XP Professional and Ubuntu Karmic Koala 9.10 on dual boot. I often get a GRUB loading failed error during boot-up. Or sometimes, when I try to boot into either Ubuntu or XP, I get a Could not read from source error.

Now this is funny. After getting one of the above errors, if I simply unplug the SATA cable from Hard Drive end and plug it again, the problem gets solved. So what and whose problem is it? GRUB or My Hardware ?

P.S.: I was suggested on StackOverflow that ServerFault is the right place for this question.