If I read your post correctly, you have exchanged the keyboard with a known good one and the one PC still does not "see" a keyboard.  Is this correct?  or have you just changed from one USB port to another or used the USB to PS/2 adapter and plugged the keyboard into the same PC? 

If you haven't tied a keyboard from another PC do that and see what happens.

Thanks for the quick reply

Yes I tried it with an known good keyboard  both a USB type and another good keyboard with PS2 connectors.  When I use the usb connections I do hear a very slight click when the key is pushed, but no letters or anything else appears on the screen. 

What happens if you boot in Safe Mode (press F8 before XP starts to load)?

If keyboard works in Safe Mode you have a software/driver issue.  

Ron 

When I start it in safe mode, as soon as I hit a key on the keyboard it freezes up, the Mouse stops working and I have to power down (Hold the power Button) to get out.

No letters ever shows up on the screen.. But it does see the F8 key when powering up to get into safe mode?

Lyle

Disconnect PC from the wall and press/hold power button for ~15 sec. Leave unplugged for maybe an hour. Then try to boot with only keyboard, mouse, monitor connected.

If that doesn't do it, you may need to run a Repair/Reinstall of XP.  The files and softwre on the system will be ok, but you will have to reinstall SP3, all 360MB of it.

Ron 

Ron,

I did notice that the keyboard would work when I put a password in....So I uninstalled the driver for the keyboard and reinstalled it and it is now working.

Thanks for all your help\

Lyle