Keyboard suddenly unresponsive. After reboot works fine

[Rincewindwiz]

Win 7 Ultimate 64 bit with all updates.


PC can work happily for many weeks then the keyboard will sulk and for no apparent reason the PC will no longer respond to the keyboard. The mouse continues to work fine.
I reboot the PC and all is fine again.
Usually happens a few times (3 so far on this occasion) and then goes away for 'several weeks'.



It can stop working within a few minutes of the reboot or continue to work for several hours before going unresponsive.


Its hardly life-threatening but is an irritation and there is always the thought it might not work after the reboot.


Any suggestions as to what is going on

 

[Megahertz07]

It can be a Hardware or software issue.
- Is it a USB or PS2 keyboard? If USB, try to put in another USB port.
- Open device manager. Is there any yellow alerts of missing drivers?

Run a disk check. Open a CMD window as administrator and type:
chkdsk c: /f
It will say the disk is in use and if you want to schedule for next start = yes
Restart

Do a System File Check. Open a CMD window as administrator and type:
sfc /scannow

 

[Rincewindwiz]

PS2 ('internal') keyboard
yes sorry - should have said done all that as standard. For the record:-

- Device manager says all is cool and the keyboard drive is up to date

- Chkdsk /F is clean

- SFC /scannow reports no integrity violations.
- Malwarebytes reports no virus

 

[Megahertz07]

What you mean by PS2 ('internal') keyboard?
Is a desktop or a laptop?

 

[Rincewindwiz]

Laptop built in keyboard - which Device manager says is PS2

Laptop (HP Envy DV6 7331SA)

 

[Megahertz07]

Please edit your specs. It says you have a desktop.

The laptop keyboard connects to the MB by a flat cable. It cam be that it has a bad contact.
Did you ever drop some liquid on it?
Don't you have a USB keyboard that you can use just to see if it also freeze when the internal freezes?

 

[Rincewindwiz]

Specs: Changed to laptop.
Keyboard cable: I know. I replaced the keyboard a couple of years ago. I have no recollection of whether the problem occurred with the original keyboard
Bad connection: Maybe but symptoms are not consistent. Bad connections are usually resolved by physical movement (and I tend to give the keyboard a fairly hard time !) not re-booting. I'll save that check for when reboot doesn't work!
Liquid - no
USB Keyboard. Yes. Normally I just reboot. Next time I will plug USB keyboard in and see what happens
Mouse works normally throughout.


It has now worked without a problem for 12 hours so maybe this particular ave of hiccups is over. I will update this thread when next it happens


Thanks for your thoughts

 

[Orcadian]

My PS2 keyboard does this after the machine has put itself to 'sleep' when I've been away. What works is simply pulling out the PS/2 connector and plugging it back in again.

A driver update didn't help and I'd guess that this old (but very fine) keyboard is now only barely compatible with Windows.

Has your machine been nodding off, and does it happen after that?

 

[Rincewindwiz]

Sadly nothing as simple as that. I rarely switch the laptop off, normally put it to sleep and its OK.
Also the problem does NOT arise when I turn the machine on. I can be typing a way merrily at the laptop's keyboard and then I suddenly notice no characters are appearing. So I have to close everything down with the mouse, reboot and start again.


I can only recall one occasion when the keyboard did not work on reboot and then it worked on the second reboot.


On the last occasion (that got me sufficiently irritated to ask this question), the keyboard 'went quiet', rebooted, worked for maybe 20 minutes, then 'went quiet', rebooted and then all OK (as it is now)

 

[Rincewindwiz]

Update: it happened again. PC doing nothing minding its own busoness. Owner downstairs making coffee. Come back to find the Caps Light on (OK so it may have been on) try to enter the password but key strokes dont register. Try to turn off Caps Lock but no response/
Plug in external USB keyboard and characters register but password incorrect (Suspect Caps Lock is overriding the USB keyboard?)
Eventually the fingerprint sensor works so I can get in.
Control panel says keyboard working fine except that it isn't working at all.
Reboot and everything os back to normal


So what is going on here