Profiles was bad enough, as Thunderbird can never open the zip file (the wording of the alternative method is gobbledegook, and there are no recognisable files if you attempt to decipher it). At least you can set all your email addresses up manually - you can't physically re-types five years of calendar entries. The infuriating this is that when you start the import, the calendar entries appear before your eyes for up to five seconds and then the program crashes ... again and again and again. I must have been trying this on and off for years now and still nobody has fixed it.