1577678 - Thunderbird deleted all email (including LocalFolders) after changing IMAP server settings

Status: RESOLVED INCOMPLETE

(Thunderbird :: General, defect)

Description

[KHorn]

Attachment: TBirdActiviityManager.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.132 Safari/537.36

Steps to reproduce:

OS: Windows 10 Pro, 1903, build 18362.295
Thunderbird version: 60.3.3 (32-bit)

link to support thread: https://support.mozilla.org/en-US/questions/1267622

The connection info for my IMAP server recently changed, so I needed to change my server settings. I:

• Opened Thunderbird
• Right-clicked on server account in left pane and selected "Settings"
• In Account Settings dialog, selected "Server Settings"
• changed "Server Name" and "User Name" fields
• Added new Outgoing Server (SMTP) entry, and set it as default

Actual results:

Thunderbird asked I wanted to Compact files, with options to "Confirm" or "Cancel". I chose "Cancel".

Thunderbird then deleted all local copies of IMAP folders as well as all Local Folders.

At first I assumed this was a case of the folders not being displayed due to index files being out of date or something similar, but looking at my profile directory, all files in {profile_dir}\Mail\Local Folders were gone, except Trash and Unsent Messages (both empty, 0KB, opening in text editor shows no contents).

Most folders in {profile_dir}\ImapMail were also deleted, with the exception of "default" folders, e.g. INBOX, Sent.

My spam folder appears to have been left intact. :/

Activity Manager shows entries for each folder (IMAP and Local) being deleted. See attached.

Some files could be recovered using "undelete" software (specifically TestDisk), however, many files appear unrecoverable, and will have to be restored from backups. I have not restored anything yet, in case the state of my install might help with debugging.

This seems like a major data loss bug.

Expected results:

Local Folders (at least) should have been unaffected by this change.

Comment 1

[Wayne Mery (:wsmwk)]

"Local Folders" (with caps) definitely has no connection in the code to any imap folder or accounts. So the fact that you lost local folders makes me immediately highly suspicious that some external software borked your Thunderbird profile. On top of that, you are on a very stable version 60. (However, your 60.3.0 is nearing a year old and should have long ago been updated to the current 60.8.0.)

What about the other files in {profile_dir}\ such as address books? Were your address books unaffected?

You really were prompted to compact? You didn't mention it in your support posting.

Comment 2

[KHorn]

I don't know what external software would have done so, but I suppose that is a possibility. I don't think that's what happened though, and here's why:

I was using Thunderbird for about a half hour immediately before I changed my IMAP settings with no problems. I had opened it up for the first time in ages (hence the old version), as I was looking for an old user id in an old email so I could reset a password to a website I haven't visited in probably 5 years. Having found the old user id in my Local Folders, I proceeded to send the reset request, and then realized that the site was going to send the reset link to the email address associated with my IMAP account in Thunderbird. This shouldn't have been a problem, since I usually access that account through a webmail client, but I had just tried to reset THAT password, and something went wrong with the webmail interface...it would let me log in but gave me some permission error and wouldn't let me see my email. "No problem", I thought, and proceeded to change my IMAP settings in Thunderbird...and then everything disappeared.

So it seems like any external software that may have caused this would have had to "strike" right at the same time that I changed my IMAP settings, which seems...unlikely.

As far as upgrading, Thunderbird gave me an upgrade dialog shortly after this happened. I have not yet upgraded, just on the off chance that leaving TBird as it was when this happened is useful in some way. As you can probably tell, I don't use it very often these days, so it's not really an inconvenience, and maybe it will help? In any case it should leave my profile dir the way it was immediately after this occurred.

{profile_dir}\abook.mab exists, but appears nearly empty (2KB and oh, Lord, it's a mork file...)

Looking in TBird in the Address Books dialog (Tools -> Address Book), it shows only 4 email addresses, all in "Collected Addresses", and the list consists of my Gmail address (for some reason...this is not address for the IMAP account I'm using), "[e-mail]", "[e-mail]", and "[e-mail]". Personal Address Book shows to be completely empty.

I was definitely prompted to compact. I definitely clicked "Cancel". I had forgotten about it until I was reading through some troubleshooting steps on the forum, and the bug submission guidelines which jogged my memory. It's possible I'm wrong about when it happened exactly, but I don't think so. I'm pretty sure (90%?) that it was right after I changed the IMAP settings.

Happy to provide any further info you think might be helpful.

Comment 3

[Jorg K (CEST = GMT+2)]

Sound more like a support request. Sure, if you haven't used TB for a long time and then change IMAP settings, it might delete folders locally which it can't see/access any more on the server. Local Folders should be untouched.

What do you expect us to do?

Comment 4

[gene smith]

When you started up tb 60.3 and before you made the imap account settings changes, did you look at Local Folders and check if they were as you remembered them to be? Anyhow, changing imap setting is completely disconnected with Local Folders (as has been stated several times before by others).

The only possible connection between imap and Local Folders is in imap accounts you can configure actions so the destination is Local Folders, e.g., when an imap message is deleted have it moved to Local Folders/Trash. But that shouldn't cause anything in Local Folders to be deleted by tb.

So, other than losing your Local Folders content for unknown reasons, I also don't see an imap bug here.

I assume before you changed your server and user name, tb was unable to connect to the server. At that point you could have set tb to "offline" mode and looked at all your old emails in the now inaccessible account, at least for folders you are subscribed to and had designated for offline storage (with default settings, everything but Junk and Trash have offline storage).

But after you fixed the server name and user name, when tb connected, it saw basically default empty folders on the server and and so got rid of (deleted) all the offline storage on your system under ImapMail. There is no warning when this occurs. It would be like when you delete a folder using a phone email app, then when you run tb it also deletes the local copy of the folder under ImapMail in your profile.

You also said that your old emails were "archived" somewhere on the imap server. Have they been put back in a location where tb can now access them using your updated account? If so, this should restore all the files in your ImapMail profile directory. (Of course, this won't bring back Local Folders content.)

Comment 5

[Wayne Mery (:wsmwk)]

Kevin's response still needed to comment 4