I upgraded the windows app this morning as requested and now it does not work. Meetings I try to join or meetings that I try to start show a "joining" circle for a few seconds and then the app shuts down. It is still in the system tray but the main window closes with no error reporting or failure message. Trying to join from the an outlook appointment directly gives the same result. Of course I had an important call this morning set up which I then had to dial into to my intense irritation.