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Upgrade losing "tags" (emails ok). Anyway to backup "tag" info?

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  • Last reply by Matt

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I've used Thunderbird for years to manage work email. The "tags" feature (where you can tag a message "important", "to do", etc) has been a main way I've managed my email. I have hundreds of emails tagged in different folders.

For the 2nd time, during an upgrade, I've lost all tags for email in my IMAP mailbox. This represents months of "to do" info for my work. The emails are all there, just no tag info.

I know tag info is stored locally and is not part of the mail server info. Does anybody know *where* it's stored so I could maybe try and back it up before the next upgrade.

This is a show stopper for me. I'll have to migrate to Outlook if I can't fix it.

MS-Windows 7, Thunderbird 45.4.0

I've used Thunderbird for years to manage work email. The "tags" feature (where you can tag a message "important", "to do", etc) has been a main way I've managed my email. I have hundreds of emails tagged in different folders. For the 2nd time, during an upgrade, I've lost all tags for email in my IMAP mailbox. This represents months of "to do" info for my work. The emails are all there, just no tag info. I know tag info is stored locally and is not part of the mail server info. Does anybody know *where* it's stored so I could maybe try and back it up before the next upgrade. This is a show stopper for me. I'll have to migrate to Outlook if I can't fix it. MS-Windows 7, Thunderbird 45.4.0

All Replies (3)

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I found an old article saying tags are stored in the "mbox file (the file with the messages)" in a X-Mozilla-Keys header:

http://forums.mozillazine.org/viewtopic.php?f=39&t=617729

But this might be old be since I don't see X-Mozilla-Keys header in my tagged messages.

I also notice that there's a new tag search option in the "quick filter". I hope a code change wasn't the cause for the loss of tags.

I also found this bug report which could be relevant:

"Rebuild Index" (aka Repair Folder) action effectively wipes tags from messages (on imap servers that don't support tags); should at least warn the user https://bugzilla.mozilla.org/show_bug.cgi?id=392510

Note, I've verified that the running "Repair Folder" *does* cause all tags to be lost in my IMAP based mail folder. According to the 392510 bug, this problem shouldn't happen on IMAP servers that support the "keyword" feature.

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According to http://kb.mozillazine.org/Tags Thunderbird "tags" are stored in a X-Mozilla-Keys header for IMAP servers which support "keywords". Otherwise they're stored locally in the .msf file.

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BenjaminGSlade said

I know tag info is stored locally and is not part of the mail server info. Does anybody know *where* it's stored so I could maybe try and back it up before the next upgrade.

It is not that simple, I with it were. Most IMAP servers these days support tags and the information does in fact form part of the mail. When it is not so, then local storage is used.

The local storage is in the MSF index files, which some of the development community call "the database" given the fast and free was folk (including me at times) recommend the deletion of MSF files to fix problems, the data is at best transitory. I see applications "thunderfix" which only deleted the MSF files in the profile. That is all it does.

I do wonder if perhaps your server is reporting it can handles tags, but in reality can not. One thing I would recommend is right clicking the folder select properties and then repair. That will rebuilt the MSF, but should respect any tag information it contains.