Left Click suddenly died on Laptop - Windows 7 to Windows 8.1.1

[DejaVu]

My missus laptops been running sluggish and hot for a while (It's a HP DV6-2020SA), so I spent Bank Holiday Monday stripping it, cleaning it up, re-pasting it (done it hundreds of times before) and then decided to give her a go at Windows 8.1.
All went well, no problems at all. Once Windows 8.1 was installed, it worked great, nice and cool. Mouse buttons working.

I thought she'd be pissed with me for not giving her the Start Button properly, so I installed 8.1.1 and Start8. All great, except since then, the Left Click doesn't work.
Tapping the Touchpad works, Right Click all good. I stripped it back down, no obvious signs of anything broke or blown. Put it back together again.

Deleted all Mouse related HID drivers from Device Manager and re-installed from Windows update. Nada.

Loaded Ubuntu Live CD. Still no Left Click... Do I re-install Windows 7 and hope it works? It doesn't work in Windows 7 Setup either!

I've read online about something about the Touchpad delay/lag that Gamers have been complaining about, but I've tried that 'fix' and still nothing (something to do with the Touchpad delay for typing purposes).
http://support.microsoft.com/kb/2907018

Has Windows 8.1 install fucked this laptop? It feels like it.
Needless-to-say, the missus is pissed and she's using my laptop for the time being.

Anything I've missed DF'ers? Anything on a HP laptop that would disable the main Left Click like a FN Function I'm not aware of?
I'm even thinking going BIOS upgrade to see if it sorts it...!

--edit
If its relevant, the buttons are part of the Motherboard (micro switches), not part of the trackpad. So can't be replaced separately.

[raelmadrid]

Has Windows 8.1 install fucked this laptop? It feels like it.

no

[akimba]

Installed Win 8.1 on me works Dell PC and me CD-Rom drive was screwed with a yellow exclamation error and the following message "Windows cannot start this hardware device because its configuration information (in the registry) is incomplete or damaged. (Code 19) "

Took me ages to get the fooking thing to work as most of the fixes on internet never worked

[evilsatan]

Does an external mouse work?

If the click isn't working in Windows 7 setup then I'd be thinking hardware failure and I can't see any software causing that.

[DejaVu]

Does an external mouse work?

If the click isn't working in Windows 7 setup then I'd be thinking hardware failure and I can't see any software causing that.

This is what I was thinking.
USB Mouse works as it should.

Just a coincidence that it screwed up while installing Windows 8.1.1 then. Bummer!

[evilsatan]

I have found RAM causes all sorts of weird problems but being random in nature it would be odd for that to be the cause here. Can you get a multimeter on the switch and check for a voltage change when using it?

[DejaVu]

I guess I could do.
Not gonna be easy, I'll strip it again in a minute and see if I can get it powered up out of the Laptops casing.

--edit
Scrap that for now. Managed to snap the Power Ribbon cable so have just ordered another one. Will replace that and try again.

[akimba]

I guess I could do.
Not gonna be easy, I'll strip it again in a minute and see if I can get it powered up out of the Laptops casing.

--edit
Scrap that for now. Managed to snap the Power Ribbon cable so have just ordered another one. Will replace that and try again.

Hmmm from this evidence me would say you broke the left click not Gatesy ;-)

[DejaVu]

Well well well.
Got the new Power Cable today. Flimsy fucking things they are. Bend 'em twice and they're a goner.

Anyway, put it all in, put it all back together to make sure its all working - nice, everything but the Mouse pad AND it's buttons. FFS!
So, I rip a ribbon cable from an old shitty PS3 Blueray drive whose lens went wonky, cut the ribbon the same width as the now fucked Mouse Pad cable (did I mention these fucking things are flimsy?) and connected it up to the laptop.

Reboot the laptop, all is good! Buttons and Mousepad working as they should.

Very odd seeing as the buttons on the Pad are microswitches on the motherboard... but changing the ribbons fixed it. WIN! Missus happy again. More brownie points for me!

[akimba]

Well well well.
Got the new Power Cable today. Flimsy fucking things they are. Bend 'em twice and they're a goner.

Anyway, put it all in, put it all back together to make sure its all working - nice, everything but the Mouse pad AND it's buttons. FFS!
So, I rip a ribbon cable from an old shitty PS3 Blueray drive whose lens went wonky, cut the ribbon the same width as the now fucked Mouse Pad cable (did I mention these fucking things are flimsy?) and connected it up to the laptop.

Reboot the laptop, all is good! Buttons and Mousepad working as they should.

Very odd seeing as the buttons on the Pad are microswitches on the motherboard... but changing the ribbons fixed it. WIN! Missus happy again. More brownie points for me!

We got a contractor at work who does that, but I am sure he breaks things on purpose just so he can fix it and justify his contract ;-)