Windows 7, keyboard not working but mouse still does

[wtigger]

Windows 7 Home Premium SP-1 on a Dell Optiplex 780, USB keyboard and mouse present. All Windows Updates completed.

Suddenly the USB keyboard will not respond. Meaning NO keypresses are acknowledged at all in Windows. Was working fine for a few months previously.

Keyboard works fine on other units. In Device Manager no issues, shows as installed and working, driver no issues, it's the Microsoft driver circa 2006. Doing "Update Driver" results in Windows telling me the latest driver is already installed.

The keyboard responds fine during POST, navigates BIOS screens normally.

Moved keyboard around to 3 different USB ports, no effect.

I installed SlimDrivers and updated ALL drivers, still no effect on keyboard behavior.

Any other thoughts?

 

[nlinecomputers]

What about PS/2?

 

[wtigger]

What about PS/2?

Unit has no PS/2 ports Would have tried that if it did

 

[Sterling Archer]

Have you tried a different keyboard?

 

[wtigger]

Have you tried a different keyboard?

Yes, two different known working keyboards.. no effect...

 

[nlinecomputers]

Have you tried to open Device Manager. Show hidden devices and remove all the keyboard and reboot?

 

[nlinecomputers]

Also have you tried system restore? Safe mode? SFC from the recovery console?

 

[ComputerRepairTech]

You check the upperfilter entries for the keyboard in the registry?

 

[wtigger]

Have you tried to open Device Manager. Show hidden devices and remove all the keyboard and reboot?

Yes, didn't work...

 

[nlinecomputers]

Are you certain it's not a hardware problem? Linux bootable cd? Using the correct keyboard in region settings? Searched for keyloggers?

 

[mr m]

Do what computerrepairtech said.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E96B-E325-11CE-BFC1-08002BE10318}/

The upper filter data should contain kbdclass

 

[wtigger]

Also have you tried system restore? Safe mode? SFC from the recovery console?

Safe Mode has no effect...

System Restore fails on all of the restore points :-(

Will try the SFC on Recovery Console later...

 

[wtigger]

Do what computerrepairtech said.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E96B-E325-11CE-BFC1-08002BE10318}/

The upper filter data should contain kbdclass

Can't do REGEDIT from Start/Run, can't type it Will try to find the executable in Windows Explorer and run it that way...

 

[wtigger]

Are you certain it's not a hardware problem? Linux bootable cd? Using the correct keyboard in region settings? Searched for keyloggers?

As I said in my original post, the keyboard works in POST and BIOS... It's NOT a hardware problem...

Did a Malwarebytes scan, nothing found, but will do more from a boot CD...

 

[katz]

The keyboard responds fine during POST, navigates BIOS screens normally.

Sounds like a windows/driver issue. As nlinecomputers suggested, run a linux/other cd (UBCD for Win - I think will permit your to work with Start/Run commands. Been awhile since I used it for that purpose...give it a try.

 

[nlinecomputers]

The registry can be mounted by other computers if you slave your drive to one.

http://smallvoid.com/article/winnt-offline-registry-edit.html

You might also be able to use the onscreen keyboard under accessibility in the control panel.

 

[wtigger]

Do what computerrepairtech said.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E96B-E325-11CE-BFC1-08002BE10318}/

The upper filter data should contain kbdclass

Got the onscreen keyboard working (forgot about it, never had any use for it before), That Registry key value is correct...

Appreciate the tips so far, but sadly nothing is working... Never seen anything like this one before :-(

Have SFC /SCANNOW working in a command window, waiting for it to finish...

 

[katz]

I recently had a similar case with a Win 8 laptop & touchpad. Nothing I tried as a fix worked. In the end I did a repair install and it has been working ever since.

You could try the tweaking all in one repair tool, that fixes a lot of oddball issues.

http://www.tweaking.com/

Or a Win 7 repair disk.

 

[The Silent Hobo]

Silly Idea, but might work.

Could try uninstalling the USB ports under the device manager and reinstalling. I've seen that happen a few times with usb items, and uninstalling the ports fixed it.

- Josh

 

[Markverhyden]

In addition to the tweaking tool try grabbing and running subinacl.exe. But to be honest my preference would be to do a bare metal unless it's going to get really messy. Especially since your tried system restore points and they all failed.