Thunderbird Just Lost All My Local Folders

[BigbirdPhila]

Just started using Thunderbird, Version 52.2.1. WIndows 10, Version 1607, Build 14393.1480. I bought the computer about a week ago.

Over the past several days I had exported my address book & emails from Outlook Express to Thunderbird. The address book imported fine, but the email import failed on two large folders. I was eventually able to individually import them successfully. It took a while, but I was able to re-create my rather large tree of folders and subfolders in Thunderbird's LocalFolders. By checking email counts I was able to determine that all the folders imported completely.

Everything was going rather well until about a half hour ago. I exited Thunderbird (File->Exit) and about 5 minutes later invoked it again. ALL MY FOLDERS WERE EMPTY! Inbox, Sent, and Trash. Everything I had sent for the past several days was gone. Additionally, all my LocalFolders were gone. The only ones under LocalFolders were "Trash" and "Outbox".

Thunderbird started to re-download all the emails on the server (pop.verizon.net). 1670 emails. Note that I am using POP. Fortunately they were still there because I have Thunderbird configured to not delete emails from the server. But all the deleting I had done from the Inbox over the past several days has to be done again.

I noticed that some of my subfolders under LocalFolders are still on the disk (even though they're not displaying in Thunderbird). Some, but not all. Of the 13 top-level subfolders I have, 10 are still there. 3 are missing. I don't know if I can trust the integrity of the ones that are still there. I also don't know how to get them back into Thunderbird. The 3 missing subfolders are not in the Recycle Bin. The newest item in the Recycle Bin is 3 days old.

I just noticed that what is missing of the subfolders is the directory in the Windows Explorer display. The directory where the local folders are stored still has two files associated with each missing subfolder (a file with the same name as the subfolder and a file with the name subfolder.msf). For example, if the "House" LocalFolder is missing, I have two files on the disk named "House" and "House.msf", but no actual directory by that name in the LocalFolders directory.

There was no power failure or error message from the operating system during the 5 minutes I exited Thunderbird and then re-invoked it. Everything appeared to be running fine.

My questions are:

1. What happened? Is Thunderbird known to do this?
2. Could it be a Windows problem? It looks so much like a clean reset of Thunderbird I doubt it.
3. How do I recover? Should I just re-import everything from Outlook Express? Delete all those subfolders still on the disk (since I don't know if I can trust them)?

I've lost my copies of everything I've sent for the last 4 days, but I think I can re-create everything else. Very frustrating. I have to figure out what happened and how to avoid it or else I can't use Thunderbird.

Any help most appreciated.

[tanstaafl]

One possibility is that something changed the local directory setting for the POP account. That specifies what directory the account should use to store its mail and message filters. Child mail folders are stored in child sub-directories of the "local directory". The local directory is normally named after the mail server. For example, if you had a POP Gmail account its usually at ..\Mail\pop.gmail.com.

Look at the bottom of tools -> account settings -> verizon -> server settings for the local directory setting, next to a Browse button. If its directory doesn't follow that convention, or the name has a numeric suffix (i.e. pop.verizon-1.net or something like that) the local directory setting has probably changed. When that occurs Thunderbird will create new empty versions of any special folders such as the inbox. Any non-special folders are not re-created, and lost. The inbox folder and any folders specified in "copies and folders" are considered special folders. Since you are in a new directory popstate.dat (it's used to record what messages have been downloaded) will not know that you had downloaded your mail, and will cause Thunderbird to download everything left in the POP server inbox again.

If this occurred your old mail folders still exist, they are just being ignored because Thunderbird is looking in the wrong directory tree for them. You can switch the local directory back to the old setting to reuse them. If you do that think about copying any new mail (that you got in the last 4 days) or any replies that you may have sent recently to a folder in "Local Folders" so that you can copy them to the inbox or sent folder in the resurrected local directory. Otherwise you will lose access to them when you change the local directory back to its old settings.

Its not clear why this type of problem occasionally occurs, but it seems to occur as a side effect of some error. Unfortunately the developers don't seem interested in looking at this problem. I suspect its a combination of its too hard to reproduce, easy enough to workaround if you know what happened, and is far less annoying for IMAP accounts. IMAP accounts are viewed as the direction to go, POP accounts will never disappear but they are basically a legacy feature. This type of problem isn't a big deal for a IMAP account as it stores its messages in remote folders on the mail server. If the local directory changes, those messages are still there.

I suggest you consider switching to a Verizon IMAP account once you've resolved this problem. See http://kb.mozillazine.org/IMAP for why IMAP is more useful.

[tanstaafl]

See http://kb.mozillazine.org/Importing_folders if rather than change the local directory setting back to its old value you'd prefer to import the old missing folders. You'd only import the mbox files (the files named after the folder, with no file extension, which have the messages).

"Additionally, all my LocalFolders were gone. The only ones under LocalFolders were "Trash" and "Outbox"."
Its local directory should be "..\Mail\Local Folders"

Help -> troubleshooting information -> open folder will open windows explorer at the profile directory used by Thunderbird. That should have a Mail directory that has child directories for all of the POP accounts and "Local Folders".

[BigbirdPhila]

Thanks for your input. I have both an SSD and an HD on my computer. In my haste to post my question, I neglected to mention that I had configured the ServerSettings->MessageStorage for my email account and LocalFolders->LocalDirectory to be separate directories on my hard drive (to get them off of the SSD). They are still the original values I had set them to:

D:\Users\Lee\Email-Verizon-<account_name>
D:\Users\Lee\Email-Local Folders

So, during this incident they have not changed.


I went to Help->TroubleshootingInformation->OpenFolder->Mail and the following folders are there:

Local Folders
pop.verizon.net
pop.verizon-1.net


However the "Modified" date on all of them is 7/22/17, not today's date, All of the files in those directories (Inbox, Trash, and Unsent Messages) have a size of 0 and their associated .msf files have a size of 2K. So, they probably don't contain any of my missing emails.

The "-1" Verizon directory might be from a re-load of the Inbox I did when I first installed Thunderbird. I remember hitting some kind of problem and getting it to download all 1600+ emails again.

So, I'm still at a loss at what happened and, more importantly, how to avoid it in the future.

[BigbirdPhila]

I figured out what happened and wanted to document it in case someone else tries what I did. As much as I hate to admit it, I caused the problem.

As I said, I have both an SSD and HD. I've been trying to allocate some of my data to the HD to avoid excessive writing to the SSD over the coming years. To provide quicker access to this area via W10's File Explorer, I decided to create a shortcut to my data area and pin it to the "Quick Access" area.

Everything would have been OK if I had stopped there. But, I felt that the default name Windows applied to my shortcut was not descriptive enough so I *renamed* it. Not a good idea.

I doubt if such an action would have bothered Linux, but Windows seems to be sensitive about what you do to links to top-level user account data areas (e.g., D:\Users\<account_name>. Instead of renaming the shortcut, W10 created a *new* directory with that name. The old directory and all its subdirectories remained and a new directory was created.

This explains why Thunderbird decided it had to re-download my Inbox: the local stores I had specified in my Options did not exist. But it does *not* explain why it also deleted 3 of my subfolders in my original LocalFolders area. I'm sure a Thunderbird developer could explain it, but it doesn't matter at this point. I decided to live with W10's default name for my QuickAccess link and all has been fine since then.

In case someone in the future tries what I did, this thread may be of some help.

[makaiguy]

Thanks for reporting back. It may well help the savvy folks that actually search for existing information before asking for help.