See: Perform a clean installation of Windows Vista
Link:
http://support.microsoft.com/kb/918884
I've installed Vista Ultimate on my hard drive which has two partitions, and deleted the windows.old file to take off XP. But, every time I boot up or re-boot I am asked if I would like to boot with Vista or an earlier version of Windows which I don't have.
Any idea what is causing this and how I can stop it so that it will just boot with Vista?

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