Calendar broken?

Hi, Thunderbird regularly unable to connect to my Google Calendar. Is there anything I can do? I updated it to the latest version today and now it said all the calendars (local, Google) are unavailable no matter what I do (unsubscribe, subscribe again and again) And if I try to create a new calendar, the Google Calendar option is not even there anymore. Is the latest Thunderbird broken or something I did? Thanks, Will