For some reason whenever I pull up Task View using a touchpad gesture (4 finger swipe down - I have a Samsung laptop with Elantech software), it causes the Win key to become sticky (i.e. simply typing 'R' on my keyboard will open up the Run dialog). It resolves when I restart or lock the computer. No similar issue when I press the Task View button from the actual taskbar.
I recently updated to Windows 10, and reinstalled my touchpad drivers, but this problem has existed since I got the laptop.
Any ideas?