By installing XP you overwrote the new Windows Boot Manager, preventing Vista from booting. Thankfully that has no effect on Vista itself or your files, settings, or programs, and is easily repaired. The first option is to click here for the command-line solution you can run from within XP. The other method is to boot to your Vista DVD and choose the Repair Computer option from the bottom left corner instead of proceeding with the installation, and then choosing Startup Repair. Either way should have you good to go in a matter of minutes.
Hope this helps,
John
I recently upgraded my windows xp home edition, to windows vista business. Everything worked fine. I only have one partition (c
and a recovery partition (d:,which i dont touch at all.) I decided that I wanted to dual boot windows xp professional and windows vista business. I created a new partition (e
(with gparted linux live cd), and booted back into vista to make sure everything was ok. It was. So then i proceeded to install windows xp on the new partition. It installed and worked, but windows xp boots up, instead of the windows vista [bootloader]. My computer starts up as if windows vista isnt installed at all. The c: partition is still there with windows vista and all my files, but the computer just boots from the e: partition. Does anyone know how i can fix this, so that the windows vista bootloader shows up when i start my computer? (or is this fixable at all without reformating my harddriver?)

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