Windows 10: All of a sudden alt-tab isn't working and I can't type capital 'u's

For some inexplicable reason, all of a sudden I can't alt+tab between windows, and I can't press shift and u to type a capital u. Every other combination of shift and letter seems to work fine, and alt and tab on their own also work fine. I've tried every fix I can find for the alt+tab issue but nothing works and I can't find anything on shift+u suddenly not working. I'm on Windows 10. It was working fine literally yesterday and nothing has changed in terms of me installing new programs or anything.

:)

 

Printer isn´t working after latest update.

After the latest update from Windows, my Canon Pixma ip6600 printer isnt working. In Device Manager it shows up as working properly but when I go to print it isn´t listed as an option in any programs. Troubleshoot suggests it´s a USB 2 printer on a USB
3 port and that that´s the problem but that cant be since it worked fine before the update. I´ve tried to uninstall and plug it back in but that doesn´t work either.

 

Cortana isn´t working

When I hit enter, it did something, but there´s still no Cortana, even after restart. So I tried it again, but now it says that it failed, because it´s already installed and it´s working in PC. So it should work, but Cortana still isn´t here.

 

alt tabbing increases system performance?

Memory problem , Nvidia had sudden FPS drop problem with first generation 320MB 8800GTS cards it is where i know this , is it back now ?
Nvidia 8800GTS and alt-tab - Epic Games Forums

alt+tab 8800GTS 320mb fixed with latest nvidia drivers yet?