* You should never install two OSes to the same partition, for it can lead to some serious problems. You didn't mention what's on D:, so installing XP there may or may not be an option, but you won't want to install it on C:.
* The problem you encountered previously is normal. Vista uses a different boot manager than XP, so if you install XP after Vista Vista will be rendered unbootable. You'll want to click here for information on restoring Vista after XP's installation. No data should be lost, and from then on you will be given the option of booting to Vista or XP.
* No, Windows cannot be installed to an external drive...thus far Microsoft has decided it's not worth the effort and risk of piracy. You can, however, install most Linux distros to an external hard drive.
Hope this helps,
John
I have a Lenovo Y500 Laptop with Windows Vista Home Basic installed. Now i like to install Windows XP. Should i install it in same Drive(C
or in D:. I have only two partitions.
Earlier once i installed XP in D:, but during bootup it didnt show the two OS. It directly used XP. I was unable to use Vista at that time.
Or can i install it in my external (USB) hard drive. If so, can i install Linux also in the external drive? But i need vista because i dont have drivers for Graphics, Bluetooth, etc., for XP.

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