OK, so I have the same problem. But, i have no idea what anybody is saying!
plus, I used a different computer in a computer block and the chip worked fine, yet on this beautiful home desktop pc the chip just greys out the port..... can somebody explain SIMPLY to me what the problem?
I have the same problem, INFACT my arduino uno was working perfectly then all the sudden i can't find my com port. not showing up in device manager so i don't know how to get the drivers re-installed if they're corrupted... I'm googling the Legacy Driver thing now