I just installed Win XP Home (upgrade version) over a previous installation of Win XP Pro. Installation went well, I did a quick format as the drive was already NTFS, and the computer boots fine . . . Except If I remove the Windows XP CD from the cd drive, or try changing the boot order to HDD first. If I do either I get the 'Error Loading OS' error. I suspect that I should have done a full format instead of the quick format. I'm hoping to avoid reinstalling again, does anybody have a suggestion?