Thunderbird is Not Responding. I have done all the ridiculous safe mode crap....which is just a time-consuming circle of nonsense. I have to think this is CALENDAR related?? I really cannot use the software without a calendar....but I am convinced that using "Lightening" and Google Calendar is killing Thunderbird. So far, I haven't had the nerve to remove both of those addons and test. I really wish I had learned how to use Outlook. I have had TB since the very first days, (post Eudora) and I have tons of archives and a profile that says it is 365 MB in size.