Whenever I do CTRL + ZCTRL + PCTRL + CCTRL + RetcIt barley works. What I usually do is hold CTRL and press the key. I end up having to press it like 5 - 15 times then it gets back to normal for a while, then goes back to me having to do that. I installed no new programs or nothing It just randomly happened. I used the on-screen keyboard and it worked fine.