Both SHIFT keys on my Latitude e6410 seem to be disabled. I have googled this problem and there are a lot op people experiencing the same problem but I didn´t found a working solution.

So what I have done until now

- Checked that Stickykeys are turned off

- Reinstalled keyboard drivers

- Loaded defaults in Bios

- Visited Keyboardtester.com , SHIFT keys were not visible

- Played with On-screen keyboard hoping that this somehow would bring my SHIFT keys back to life again.

All of this didn´t fix the problem.

BUT something strange happens when I press both SHIFT keys at the same time in combination with keys ´z´, ´x´ or ´c´.

2xSHIFT plus ´z´ is like pressing the TAB button (Keyboardtester.com shows TAB and ´z´ key are hit)

2xSHIFT plus ´x´ is like pressing CAPSLOCK result on screen XxXxXxXxXxX when repeating this action (Keyboardtester.com shows CAPSLOCK and ´x´ key are hit)

2xSHIFT plus ´c´ is like pressing CONTROL- F or F3 which shows a search box (Keyboardtester.com shows F3 and ´c´ key are hit)

Solely pressing both SHIFT keys give no reaction and all other keys in combination with the SHIFT keys don´t lead to any visible action as well.

This makes me think that this problem must be a software problem and not a hardware problem because there is a reaction on pressing the SHIFT keys simultaneously in combination with ´z´, ´x´ or ´c´. 

Does anyone have an idea what causes this bizarre behavior and even better, how to fix this ?

TIA Beppie