Status of MailDir

Discussion of general topics about Mozilla Thunderbird
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Joined: October 20th, 2017, 11:35 pm

Post Posted October 20th, 2017, 11:44 pm

I am very keen to convert my Local Folders to MailDir format and put all my emails saved over 20 years into it. This is primarily so that I can backup my emails automatically with a cloud backup.

However, having read various posts over its history, I see that there are still a few bugs left and it's not yet completely ready for mainstream use - correct?

My question is simply how not ready is it? I am a user with a technical background. I don't mind if the odd thing doesn't work or I have to use a workaround or if after I convert, Thunderbird crashes once a week.

I really do mind if my emails get corrupted or I lose an email. Are the remaining bugs relatively innocuous / slightly inconvenient? Or would you advise waiting a bit longer yet?

Thanks for any advice/input/experience...


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Joined: July 30th, 2003, 5:06 pm

Post Posted October 22nd, 2017, 4:43 pm

Thunderbird doesn't have a real maildir implementation, its more of a maildir-lite. See . "You cannot point a Thunderbird account to a mail server directory. You do not get message flags stored with emails. You only get a single file per message, and nothing more."

I've been using maildir for offline folders on a gmail and a fastmail IMAP account for about a month with no problems. The other 6 accounts use mbox. However, I've had little reason to move/copy messages between mbox and maildir accounts. My impression is that you can avoid any serious maildir issues if you aren't moving/copying messages between maildir and mbox based accounts and don't do something behind its back (such as move messages using windows explorer or delete a folder on the IMAP server using webmail) but I don't have enough experience using maildir to be sure.

I have run into some gotchas in the design. My IMAP accounts server settings are set to use "when I delete a message : just mark it as deleted", rather than moving it to the trash. I normally can see and use a deleted message, it just has a line drawn through it in the folder listing. When there is too much clutter I compact the folder, which physically removes the deleted (but not hidden in this case) messages. I can't do that when using maildir based accounts. I expected them to remap the compact folder command to expunging each deleted message. You're less likely to run into gotchas with a POP account because of its limited functionality.

I suspect waiting another 6 months would not make a big change as the main problem holding up it getting more mature is that its not used widely enough. There also aren't enough threads about maildir related problems in this forum to get a good feel how vulnerable it is to configuration specific problems.

I suggest that if you try using maildir you "enable leave message on server" and "for at least 30 days", but disable "until I delete them". That would make it easier to detect problems and recover from them. I'd also do periodic automated backups of Thunderbird. See ... d_services

The ImportExportTools add-on knows how to import a maildir folder.


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Joined: November 13th, 2005, 9:58 am

Post Posted November 11th, 2017, 4:08 am

I've been using Thunderbird with maildir exclusively for about one year without any problems. It's very fast and reliable. I followed the suggestions presented on ... ir.389599/ . They worked flawlessly.

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Joined: October 20th, 2017, 11:35 pm

Post Posted December 3rd, 2017, 5:34 am

Thanks. V. helpful; particularly the suggestions link. I'm going to give it a go.

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