First time poster at the end of my rope with this issue. I recently upgraded my laptop CPU. I used a processor that Dell had tested on my specific model of laptop (N5050) and everything was fine for about 2 weeks. I used ESD protection and didn't do much actual touching of the motherboard. About a week ago the laptop did a hard shut down for no apparent reason. There was no BSOD and when my system booted it didn't prompt me to go into safe mode. However once I got to the Windows profile screen the keyboard was not responding. The HD is new, the system is about 5 and a half years old.
The keyboard works fine through POST, Windows sees it and is not displaying any errors in device manager. I got the keyboard working again by rolling back Windows to just after I installed the new CPU. However, when I let Windows update run tonight the keyboard stopped working again. I rolled Windows back and it is still not working. I have un/reinstalled the driver as well as trying several restore points. The ribbon is firmly in the port. The keyboard is still working through POST and in BIOS but as soon as the OS begins to load it is no longer active even though device manager shows it is active. My anti-virus is not finding anything and I don't use the laptop for anything that is risky for malware (no porn, torrents, opening strange e-mail attachments, etc.).
Any ideas what to try next? I really don't want to reinstall the OS.
Edited by scottm704, 03 November 2016 - 03:09 AM.