I updated to 64bit and lost 3 years of emails back to 2016 for current folders.
I updated Thunderbird to 64bit. When I ran it, I only had emails up to 2016. In some cases, if the folder was a new one then the emails to 2019 are there. Many folders are missing. Also, my address book is the same way. Two days ago before I did the upgrade, AT&T changed their servers from att.yahoo to att but I don't think that damaged anything since this was before the Thunderbird upgrade.
Modified
الحل المُختار
go to the about:profiles entry in the troubleshooting information (Help menu)
Select the profile listed that is not your current default profile and make it the default and restart Thunderbird.
Read this answer in context 👍 0All Replies (2)
PS. I found a backup profile from 6 months ago. I moved the latest profile to a temp directory (just in case) and put the backup profile in. Same problem.
الحل المُختار
go to the about:profiles entry in the troubleshooting information (Help menu)
Select the profile listed that is not your current default profile and make it the default and restart Thunderbird.