https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer
Sunday, January 24, 2016
Moving Thunderbird data to a new computer
As I've been chased from mail app to mail app and old computer to new computer at work, I've saved off my email into various formats. My current format is Thunderbird, which is actually a terrible choice because the mail is stored in non-human-readable "database" files that seem to make cabbage of the data inside them. Nonetheless, I have to accomplish the task of transplanting my Thunderbird files from my old computer to one of my new ones. So far, everything I've found seems to indicate that it's simply a matter of taking the database file from the old system and opening it on the new system. I wish I had more confidence in that assertion. Some links:
