how to install xp to toshiba A200 satellite with vista..?

[mheavan]

please anyone here help me .............I have a vista on my toshiba A200 satellite laptop....I had a tough time with this vista...i preferred to install xpwhen i tried to do so...during boot session it came a s "HARDDISK NOT INSTALLED"i searched in internet and i found many solutions but none worked for me can any one pls guide me...............i will be thank full to you.............