When I type letter (characters) numbers are displayed.

[jason2074]

Well actually he or she didn't mentioned both. But since it was mention about changing or added(?) another antivirus security made it go away, It could be possible that it was this from Comcast and perhaps the OP could enlighten us here... It was mentioned/suggested on  some threads and it made the same symptoms or behavior after using another PS/2 or USB keyboards.

[Geek-9pm]

Well actually he or she didn't mentioned both. But since it was mention about changing or added(?) another antivirus security made it go away, It could be possible that it was this from Comcast and perhaps the OP could enlighten us here... It was mentioned/suggested on  some threads and it made the same symptoms or behavior after using another PS/2 or USB keyboards.

So you say some security programs used together abuse the Keyboard Service process? Where did you see that?

[Geek-9pm]

Answer my own question.
Found on Tom's Hardware.

taxesgal   06-05-2011 at 03:45:35 PM

Thank you so much for this info. After checking with several PC guru's no one had the right solution, but yours worked for me, with a few modifications.

I'm running windows XP and downloaded Comcast's Constant Guard to get Norton Security Suite. It corrupted my keyboard as you said, HOWEVER it corrupted all applications and programs.

SOLUTION:
I went to control panel and uninstalled Constant Guard. The uninstall removed the Constant Guard components but left the Norton Suite. I didn't have to do anything further The keyboard works, Norton works.

http://www.tomshardware.com/forum/79182-45-keyboard-letters-coming-numbers

Appears to be at least two users who claim  'Constant Guard' is the problem.