I recently moved my Thunderbird account from an old computer to a new one where I use Thunderbird 8.14.0 on Ubuntu 21.04. Everything works apart from the address books: e-mail addresses don't show up in autocomplete when composing messages and the address books themselves don't show any entries either before or after a search, but e-mail addresses with which I have previously communicated are marked by a full star indicating that the address book information is available to Thunderbird at some level. When I first looked in the account folder I found no *.mab files but only *.mab.bak files. Copying these and renaming them to *.mab seems to have no effect when starting Thunderbird afterwards. There are also *.v2.sqlite files with the same names as the address books themselves as well as *sqlite and *.sqlite-wal files. The latter two groups of files are the only ones to see regular modifications but the *.sqlite-wal ones are 0 bytes in size. Could this be a permissions issue? The profile folder is on an NTFS partition by default (where I only access it from Ubuntu). I've also copied it to my home folder but that doesn't seem to resolve the issue (at least not by itself). Whenever I start Thunderbird the following gets added to my profile.ini: '''[InstallAAAAAAAAAAAAAAAAA] Default=/pathtoNTFSfolder/xxxxxxxx.default Locked=1''' where I've replaced title in brackets, path, and profile name. An analogous text appears when starting the copy of the profile in my home folder. The last thing I tried was to rebuild the global database. This took a while but also had no effect. I'd much appreciate any advice. Having to type each address by hand each time I compose a fresh e-mail isn't very convenient. I'm not worried about the content of any of the address books and happy with rebuilding a new history address book from scratch if need be but would appreciate help with that as well.