Your drivers might have become corrupted if there was a crash. Check under your device manager for a yellow exclamation point for troubleshooting. Is the port displayed under your connectins?
If not, you may try a fresh install. Delete the port either from your device manager or from the add/remove hardware and reboot. Your computer will redetect it and install a fresh set of drivers.
My gaming machine:
P4 2.8 GHz
2 X 512 MHz PC3200 in dual DDR mode
Intel D865PERL MOBO
integrated 6.1 MAX audio
Logitech duo MX mouse and KB
ATI RADEON 9800 PRO