Brand name and model number of computer??, Whether you have a full, legal, XP SP2 disc to install with?..Have you got the SATA drivers if your HD is SATA? Things you have already tried? Download and copied ALL of the XP drivers for the hardware components of the computer?
In the meantime, see the discussion at the link below for others that have performed the same steps. Read all of the posts.:
downgrading from vista to xp
Paolopaed, I Recently Did It This Way..
http://forums.cnet.com/5208-12546_102-0.html?forumID=133&threadID=243153&messageID=2461470#2461470
Hope this helps.
Grif
i am trying to reinstall xp on vista in order to delete it.but when it starts booting, at a prticular point it brings out the message that windows cannot find the hard drive disk or cannot find the setup command.pls help for i need to install the xp badly.tanx in advance

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