Just to confirm..Control Panel/System/Device Manager... Modem does not exist in the list of hardware ? or is there a yellow exclamation mark against the word Modem ? My inclination would be to go inside the computer and physically remove the modem (computer turned off !! ) restart the computer then turn it off and replace the modem in the same slot and restart computer again. It should now recognise the new hardware & you can re-install drivers.