I was experiencing the same problems and came across the solution that worked for my Lenovo Y550 laptop. Here it is:
Typed letters appear as increasing numbers ( 0,1,2,3,4,5). When I type letters they appear as numbers which increase instead of letters.
This issue could be caused by a software program called GuardedID. Follow the steps below to prevent the application from starting up or you may remove the application if you want to.
To prevent GID application from Starting Up:
Click Start
Click Run
Type "msconfig"
Select "Startup" tab
Unchecked GID desktop application
Press OK then reboot laptop.
or
To uninstall GID Application from Windows
Click Start
Click Control Panel
Click Add / Remove Programs
Search for "GID" / "GID Desktop Application
Select the item and select uninstall
Reboot when uninstall is done.
Hope this helps those coming to look for help!
