i just recently had the exact same problem, it was because i upgraded from a windows 2000 professional installation.
it can also happen if you use a copy of windows xp, for some reason sometimes when you copy them all the files dont get copied, are you using a copy? or did you upgrade from an older version of windows?
i just reinstalled windows xp from a legit disk and it worked fine.
then did an upgrade to xp pro from a copied disk, he he. if for some reason the things i mentioned dont work do a search on google and type in "ntdlr is missing", and a whole bunch of things will pop up to help you..
let us know how you make out.
ASUS A8V Deluxe MOBO rev 2
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