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I'm an Ubuntu user and I've installed Win XP and Ubuntu on my 32-bit Acer Aspire One. I've once restarted and I get this
error: no such partition Entering rescue mode... grub rescue>
(hd0) (hd0,msdos5) (hd0,msdos3) (hd0,msdos2) (hd0,msdos1).