Urgent help needed with gui

I would not so much be annoyed if it would not render impossible to bind new keys or the selection of a plane when playing online.

After a while this happens to ALL popup windows (yes, those of the graphical user interface, not those during flight). Also those in the options or when confirming exiting the game.

Reinstalling did not help.

So I would like to try reinstalling the redist folder programs. Can somebody instruct me on this?