For starters, I am currently running version 52.3.0. I'm not certain when it last upgraded, but I seem to recall it was within the past week or two.
A few days ago, when I opened TB, I received multiple popup error messages about various local folders being missing so filters that used them would be ignored. I looked on the lower left, and none of my local stored folders were present. I shut down TB, rebooted and checked my C: disk (where my profile is stored) for errors, and rebooted. After rebooting the result is the same - still no local folders so I started digging deeper.
To be clear, there are still local folders on the side of the screen, but only the default Sent, Junk, Trash and Outbox. Junk, trash and outbox are empty, but the Sent folder is populated with messages I sent so this is potentially a good sign that everything isn't gone.
I checked the profile folder, and the Local Folders folder is present and populated with appropriately named files and folders. I also restored the profile from a backup that was a few days old, and the two folders appear to at least be similar, although I haven't yet done an actual comparison.
I checked Account Settings, and the Local Folders "account" was pointing to the correct profile folder, the one I verified above. As a check, I tried changing the folder temporarily to the restored backup. I was able to change the directory path, but this did not restore the folders. Since neither the current nor the recent backup seemed to be working I tried an earlier backup. I restored a 9/20 backup to a temp directory, and pointed the local folder account to it. This worked just fine from the temp location so I deleted the current default\local folders folder and replaced it with the working backup.
I tried to set the local folder path back to the default, but when I tried to change back to the default folder I received an error -
This seems odd since the folder I'm trying to access was in use until minutes earlier when I changed it for testing. I tried moving the local folders up a level to the top level of the profile folder but this produced the same error. Finally, I moved it to the Profiles folder, and it worked.The Local Directory path "C:\Users\username\AppData\Roaming\Thunderbird\Profiles\2vfw5vt9.default\Mail\Local Folders" is not suitable for message storage. Please choose another directory.
It seems that TB will not accept any folder located in the actual profile. Is this a recent change, or is something not working on my end?
If this was an intentional change, it was apparently handled terribly by the update. There should have been some indication with an offer to move the folder rather than simply making it stop working.
