How to fix arbitrary keyboard navigation?

Question

Iron

The user has a very strange situation, he arbitrarily (well, at least he says that it happens for no reason at all) keyboard navigation is turned on. Those. when you type text in Word, various menus open instead. Also weird mouse behavior. Double-clicking on a file with the left mouse button does not open the file, but opens the properties of the file! I thought about the sticking of the Alt key, but in general I changed the keyboard to a guaranteed working one and the same story continued. When the computer is restarted, this strange behavior disappears. Can anyone please help!)