I have a (large) number of strangly corrupted local folders in Thunderbird. As far as I am aware, all emails in these folders are currently displaying correctly. They are shown in the folders, and I can open them and read them. However, all or almost all emails in these folders disappear if I apply any of the following operations to the containing folder:
- repair folder (context menu > Properties > Repair folder)
- export folder as mbox-file and reimport it (using ImportExportTools addon)
- close Thunderbird, delete *.msf file associated with the folder, and restart Thunderbird
(I've also tried migrating the folders to Evolution, in several different ways, but this is perhaps a different story. The best result I have been able to obtain is equally strange: I can see the migrated emails on the disk, but Evolution displays the folder as empty.)
Does anybody have an idea what might be going on? Is there a way I can “repair” my folders without losing my emails?
system: Ubuntu 14.04 software: Thunderbird 45.3.0 Account Settings > Local Folders > DiskSpace: Don't delete any messages. > Message Storage Type: file per folder (mbox)