Otherwise NTLDR will override the Windows Boot Loader causing Vista to be unbootable until you repair it. It can be done either way, but it's far less of a hassle if Vista is installed last.
And you are correct with regards to program installation...you'll have to install it once on each OS. Just be sure you have licenses for two simultaneous installations.
John
Am planning on dual botting. Which operating system should be installed first, and 2nd, if I am right any programs, antivirus etc that I want to use on both XP and Vista will have to be installed on both. Thanks in advance
Richard

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