If I Subscribe to a folder, and then restart, the folder appears for a second and then disappears. There are no errors in the error console with timestamps at the moment that it disappears.

I had no problems until today. My problem may be slightly more complex. I set up Thunderbird and it was working fine. Unfortunately my e-mail provider is GoDaddy, which now provides Outlook for mail. They just switched me over and there have been multiple problems. I called about a problem yesterday. In the process of "fixing" it, they reset my password. They said I could just switch it back. That was not true. They changed the password policy to require 9 characters, in the past it was 8.

I logged into Thunderbird and it complained the password was wrong. So I entered the new password. Again, it said it was wrong. At this point I was seeing all my folders. I tried again. This time, it let me in, but all my folders vanished when ThunderBird updated the INBOX. I see new mail in InBox, but no folders. On top of that, the folders in AppData have been deleted, i.e. I had ATT and ATT.msf, the former is gone.

As discussed by endolith, I tried to subscribe to the missing folders. I see the list of all the folders, but subscribe then OK- nothing happens.

I tried some debugging and things got worse- unsubscribe from all the folders. All the msf files go away. Resubscribe to ATT- ATT.msf comes back, but nothing downloads. Resubscribe to the rest- nothing, the lost msf files do not come back.

I have Thunderbird ask me each time whether to make it my default e-mail reader.

Also as discussed, Thunderbird initially shows the folders when I restart it and the prompt to Set as Default comes up- then they go away when I say skip.

I created a new profile for the same IMAP account. That way I could give it the new password from scratch. I subscribed to all my folders. The msf files show up. If I go to AppData I see them. But nothing downloads. When you go to Options-> synchronization->Advanced, none of these folders show up.

Getting force to move to Outlook was bad enough, but these Thunderbird problems are pushing me over the edge!

I did save a copy of the profile. But just copying in the mail files does nothing. For some reason they are called ATT-1 and ATT-1.msf, in addition to the ATT.msf. I see that in another e-mail account I set up. At this point I am afraid to even open that one in Thunderbird- it had GBs of mail in folders.

One more note-

I copied the profile over that I had saved. It comes up, though the password is wrong. All the folders are there displayed in the interface and the folders are in AppData. As soon as I enter the password- no folders are shown and all the files are deleted from AppData.