Keyboard not working in Excel

[SimonHughes]

This is not necessarily an Excel question but I am hoping for help. My keyboard is not functioning in Excel!. It works on Word, PowerPoint, Search functions and even keyboard shortcuts (such as Alt+Home etc) but nothing else can be entered. I had made some entries on two worksheets and on the third this was not possible. I naturally checked to see if I had accidentally protected the sheet and I had not, I tested against a new and other existing worksheets and still no entries are possible.

Any help appreciated.

 

[SimonHughes]

Whoa! I just quit and restarted Excel and the keyboard worked again, but this was a very strange incident - any ideas what could have caused it?