hhhmm.. when i Nlited my Windows XP (512Mb, i did not removed the network or modem drivers, if you could only re-do the process and do-not remove those modem drivers re-install xp (or perhaps fix it) this should fix the issue easily

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modem drivers are different from modem support (of windows). you can remove the drivers and can still use the drivers that comes with the modem, but if you remove support, you will need to redo the nilte cd then reinstall since no matter what you do, windows won't recognize the modem, regardless if you have the modem drivers or not.