iPad 2 - USB Device Not Recognized on PC

I have an iPad 2 GSM with IOS 5.1.1 which I want to upgrade to IOS 9 (about time, I know).

When I connect it to the computer (doesn't matter USB2 or USB3 port) I get "USB Device Not Recognized", so I cannot connect it to iTunes.

I have Windows 8.1.

iPhone 4G and iPhone 6 connect without issues and are detected by Windows and iTunes.

I tried:

- Installing iTunes again

- Installing Apple Mobile Device driver again

- Uninstall and reinstall Windows USB drivers

- Tried different cables (original and eBay stuff)

- Tried all ports on the computer

- Tried to reset all iPad settings

- Tried on different computers

Nothing works - still get "USB Device Not Recognized (Device Descriptor Request Failed) - error code 43".

My latest iTunes backup for this device is from June 2015 and since then I haven't tried to connect it to USB, only recharged it with the wall adapter, so I had no idea this issue started to happen until a few days ago.

The iPad recharges with the original charger or through computer USB, but I can't use it for syncing.

Oh, and I can't sync through WiFi because I reset iPad settings so it lost the ability to connect to my iTunes through WiFi.

I really have no idea what to do next...

I'll appreciate any help with this... I don't want it to become a paper weight or worse - door stopper...

Thanks!