I have a WinXP Pro system. I used to run ThreatFire on it but decided to uninstall it. Everything went smoothly but when I restarted my computer the keyboard stopped working (under XP, it worked before XP was loaded).

I tried F8/Safe mode/Last Known configuration but none worked.

Fortunately, I was able to use remote desktop to login.

I tried system restore but it could not proceed.

I looked at device manager and it reported code 39 (corrupted driver). I uninstalled the driver and rescanned for hardware. Same problem.

I copied kbdclass.sys and i8042prt.sys from another Xp computer to System32\drivers. Nothing changed.

Finally, I decided to do an XP repair install (big mistake!)
Everything went well but then it asked for product key to finalize installation and the keyboard was not working.

I contacted the custom service from PCtools and I was told to look for TFkbmon in the registry.

I have UBCD4win available so I was able to search the registry but did not find one. Furthermore, UpperFilters value looks correct. HKLM\SYSTEM\CurrentControlSet\Control\Class\{4D36E 96B-E325-11CE-BFC1-08002BE10318}:UpperFilters = "kbdclass"

I am running out of ideas. Since the keyboard works find under BIOS/Live CD but stops working once "Windows setup (repair install)" is loaded, I would guess the culprit is an old file not updated during the repair process, but I just could not pinpoint it. Is there any other thing I should try?

Well just to check from the beginning: are you opposed to wiping the partition and doing a clean install?

Also is this a manufactured computer with an OEM CD or a home build with a retail CD?

Hi, Thanks for the reply. I am not inclined to do a clean install now since the problem might be fixed by just a registry tweak. The computer is a Dell but I have a retail XP.

Just to clarify:

Was the previous version of XP the Dell version or did you previously have a retail version installed?

What is the exact Dell model?

Do you have their CD's?

When does the keyboard fail?

For example can you press F6 to load drivers?

I probably did not make it clear. The keyboard is fully functional. I tested it on other computers and it works under BIOS/DOS/Live CD. The problem was when Windows loaded, the keyboard stopped working.

I tried to do a repair install with retail XP pro ( DEll dimension 4160 with XP pro preloaded) but I could not type in the product key due to keyboard problem (it worked at the beginning of the installation process).

You were quite clear I was just wondering if you could press F6 to load drivers.

My premise is that your Microsoft XP is overwriting Dell XP specific functions / drivers.

On more reflection even if you could load the Dell drivers at F6 the Microsoft CD would alter them.

These CD's are not the same and Dell is very proprietary.

Hence the question as to whether the previous install was a Dell install or a Microsoft install.



That being said:



Depending on the above questions / answers:


The most expedient solution is probably to use the Dell CD's or recovery methods for that computer.


If you wish to install a Microsoft Retail version then wiping the drive prior to a Clean Install is most likely necessary.


I cannot find a Dimension 4160 at Dell:

http://support.dell.com/support/topi...gen&redirect=1




...

Sorry, it should be Dell dimension 4600. The keyboard is a generic one and I was told by Dell tech support that XP's default driver is sufficient. I understand I can go to the reinstall route but I want to use that as the last resort.

Did you mention to either Dell or PCTools that you were using a Microsoft CD?

Do you not have the Dell disks?

Here is the Dell reinstall wizard covering various methods using their software:

Dell - Support