Issues with win key and right alt key after Windows Update (Polish diacritical signs not working)
Solution 1:
OK! After two days of struggle I've managed to reclaim my diacritics :)
The reason for this issue is: Synaptics device driver! To remove the issue simply go to Control Panel > Add or remove programs > Remove Synaptics.
After that go to Windows Update, search for new updates and this will try to install the driver again. Instead of installing the update - HIDE it. After security prompt the driver will appear grey'd out and the issue is solved :)
Information confirmed with Microsoft Support.