RAS

I have been attempting to install RAS on NT4.0 SP6. I can install the modem okay, I have installed and re-installed RAS several times and then the service pack again to no success.But I still get the modem not found error or something close to that. Can I re-install software in the OS that specifically points to the modem etc like maybe the modem.ini or??? if so How? I feel I have exhausted all other Tech Net solutions and still have no dial up. I am trying to rule out a mother board problem .. I do not have any IRQ issues and the COM port works for COM 1 on the UPS but will not work on a modem installed internally or externally.
Help!
Thank you in advance!