I happened to short-circuit my Arduino by mistake. It was powered by USB on my Windows 7. The OS was so smart to pop-up warning about USB power surge and shut it down immediately. Arduino survived.
I fixed the circuit and connected it back. Arduino was powered again, but it was not recognized as COM port anymore. There was no unknown device in Device manager. I tried different USB connector on the same computer and it was found and it worked. But the other USB was out.
I restarted the computer and connected the Arduino back to the broken connector. The drivers were automatically reinstalled (I don't know why) and it worked again.
Is it possible to re-enable Arduino on the same USB connector without restart? I'd like to understand what happened on the computer side.