I have a strange problem. Last week my keyboard just stopped working. The lights were still on (Logitec G15) so I know it had power, but pressing the keys gave no results. I have since tried to swap in other USB keyboards, and have even connected a Logitec keyboard via the unifying dongle (Connected correctly, but typing on keyboard gave no results). So I have tried multiple keyboards, I have tried a system restore to a point when the keyboard did work, and I have tried updating drivers. Nothing seems to work. My device is connected to the computer, but typing displays no results on the screen.
Additional information: I have opened device manager, and it seems that plugging in the HID compliant keyboard generates not 1 but several entries there, and all of them have the "!" trouble indicator next to them. I tried to do a system refresh, but windows said I was missing files in spite of the fact that I had made a recovery USB stick (That it then didn't recognize).