Well, what changed between the time things worked and the time they
didn't?
You've told us nothing about your computer and its keyboard. Laptop,
desktop, usb keyboard, plain vanilla ps/2 keyboard?
Any special keyboard or "hot keys" software running?
It can be very hard for a non-technical person to know what to include
in a post to a tech support newsgroup. Here is a link that will help
you with that - http://www.dts-l.org/goodpost.htm