Re: Studio 17 Keyboard problem (solved already)
Thank you for posting this, you've made it to the top of google for "dell studio keyboard stopped working" which means I got mine working again about 20 mins after it stopped!
I have a 3 month old studio 1555 and in the middle of using it, the entire keyboard went dead. No keys worked whatsoever. After a couple of reboots which didn't fix anything, I used the windows onscreen keyboard to log in and search google. Followed the steps in the OP exactly and hey presto! Working keyboard!
Just out of interest, did anyone notice their laptop was quite hot when it stopped working? Mine was.