Programs in Windows 7 Hang (Not Responding) after Keyboard Input

I have a custom-build PC that is a couple of years old. We had some storms yesterday while I was at church. When I came back, apparently the power had gone out because the PC was off (I leave it on 24/7). The battery is dead in my UPS, so when I booted it up today, I got the request to "start Windows normally." Once I logged in, I noticed a strange issue happening...

I can run any program just fine using the mouse. However, as soon as I start typing on the keyboard, the particular program I am using hangs and becomes unresponsive. However, all other programs continue to function just fine. But, if I switch to another program and start typing, that program will lock up, as well. I can continue to use the PC and any programs as long as I don't type on the keyboard.

I figured that lightning must have hit the keyboard, so I replaced it with another (PS2) keyboard. The same thing happened with the alternate keyboard. At that point, I figured that the PS2 port must have went out on the motherboard, so I plugged in a USB keyboard. Again, same thing...

I started testing various programs and found that the Windows system programs (Command Shell, Notepad, Explorer, etc.) are not affected by this issue. It seems to only affect programs that have been installed (Office, Adobe CS, WLM, etc.).

Following the advice of this thread, I rebooted into safe mode (with networking) and did the same tests. Not a single program locked up when I used the keyboard in safe mode.

Any suggestions?

I just ran

Code:

sfc /scannow

(while in safe mode) and got the following response:

Beginning system scan. This process will take some time.

Beginning verification phase of system scan.
Verification 100% complete.

Windows Resource Protection did not find any integrity violations.

OK, I guess the scan in safe mode fixed the problem (even though no problems were found). I rebooted and all seems to be working fine, now. Sorry, I can't say what the solution is...I'll post again if the issue reoccurs.

Facing same issue.
System works fine as long as keyboard is not used. But press a stroke on keyboard and whatever is open in front of you hangs.
Be it the start menu, file explorer, office etc....
Issue is random and appears once a day at least.

I have been using same copy of windows with same drivers since 3 years and no issue.

And by the way, no issue on windows 8.1.

just had a freeze again, so uninstalled Root Hub drivers and restarted.
Let's see....

Uninstalling Root Hub Drivers didn't work.
Unistalled the keyboard and restarted but it hanged again after a while.

Frustrated....
Installing 8.1 for now. With (Classic Shell+Oldnewexplorer+8Gadget pack)

myaeger said:

I just ran

Code:

sfc /scannow

(while in safe mode) and got the following response:

Beginning system scan. This process will take some time.

Beginning verification phase of system scan.
Verification 100% complete.

Windows Resource Protection did not find any integrity violations.

damn....
Looks like it fixed mine problem too.
It didn't find anything but system is working fine now.
Reinstalled OS 3 times and still ended up with same problem. But after running sfc /scannow command it is working fine.