[Dovecot] Can't create subfolders of my INBOX or delete folders with IMAP

[Josh Burley]

I had the same problem. When creating a new folder that should contain 
subfolders, I appended a trailing /. This would enable the folder to 
contain subfolders. And only leaf nodes could contain messages.

Along that same line, Thunderbird was trying to put folders into the 
Trash folder upon deletion. Which wasn't allowed (as far as I can tell) 
because the Trash folder was a leaf node, and could only contain messages.

If I tried to delete a folder in Outlook, or a webmail client, it 
deleted it correctly.

.josh

Matthew Exon wrote:
> Hi,
> 
> I've been using the dovecot IMAP server for about a year now, and 
> basically it works.  But there's an annoying problem, that I can't make 
> any subfolders.  I can only make folders that are at the same level as 
> my INBOX folder.  Worse, I can't delete folders once I've created them.
> 
> I'm using Debian unstable on both the server machine and my client 
> machine.  The dovecot version is 0.99.13.  For my mail client, I'm using 
> Mozilla Thunderbird version 1.0.
> 
> I've done a bit of investigation on my filesystem, and by googling for 
> all kinds of stuff, but I'm really drawing a blank on this particular 
> problem.  Most of the general linux email documentation I've found 
> either doesn't mention IMAP, or doesn't mention dovecot, or both.  I can 
> barely find any references to the concept of "subfolder" at all.  I 
> really don't want to know anything about email servers, I just want the 
> bloody thing to work.  Trying to figure out what the hell's going on is 
> really frustrating!
> 
> On the server, I seem to have various mailboxes distributed around the 
> place.  I've got a mail box in /var/spool/mail.  I've got a file ~/mbox, 
> which seems to be very old and is therefore probably a red herring. I've 
> also got a directory ~/Mail with a bunch of files in, one for each of my 
> folders.  Having some of my mail in /var/spool, and some in my home 
> directory, seems a really horrible way of arranging things, but anyway...
> 
> Various online sources seem to suggest that maildir is better than mbox. 
>  I don't have any particular preference for one or the other, but I 
> don't want to change if I don't have to because:
> 
> 1) From experience, I don't screw with settings if I don't have to. 
> Debian made it that way, and changing it behind Debian's back is a 
> surefire way to cause trouble later.
> 
> 2) Any other accounts on that machine (especially ones I might create in 
> future) will probably still be mbox, causing even worse confusion later.
> 
> 3) Porting mailboxes is always risky, and I don't want to lose my mail, 
> or have incoming email dropped, or accidentally corrupt it, or anything 
> like that.
> 
> So I'm not going to do any of that unless I'm sure that it's actually 
> going to fix the subfolder problem, and until now I haven't found any 
> information anywhere to guarantee that that's the case.  Intuitively I 
> can guess that if a folder is just a big file full of concatenated 
> email, then making a subfolder is going to be pretty much impossible, 
> but I don't want to guess here.
> 
> The actual symptoms in thunderbird are:
> 
> When I select "New folder...", I get the "Create as a subfolder of:" 
> dropdown hierarchy box thingy, but the "Inbox" option is greyed out 
> (side complaint: no user interface should ever have a greyed out option 
> without providing an explanation as to why it's not available, and what 
> you should do if you want it to be available.  Displaying it like that 
> is just cruelly teasing the user).
> 
> When I try to delete a folder, I get a dialog box saying "The current 
> command did not succeed.  The mail server responded: Mailbox doesn't 
> exist: <name of folder>".  This is pretty frustrating, because I can 
> *see* the damn thing in thunderbird.  (another side complaint: "The 
> current command"?  You're *running* the bloody command, you should have 
> a better description than that!)
> 
> For some reason though, I can rename a folder with no problems.
> 
> I went into /var/log/ on the server, to see what was in the Dovecot log 
> file about the server errors above, but there *is* no log file, nor 
> anything in the syslog.  That can't be good.  How do you tell the 
> sysadmin when there's a problem?
> 
> Does anyone have any suggestions for how I can fix this?  And if 
> possible, I want to fix this the Debian way, that is by modifying a 
> debconf setting or a /etc/default file or something like that, so that 
> when I upgrade Debian, or uninstall dovecot and then reinstall it, it'll 
> be handled gracefully.
> 
> Thanks,
> Matthew Exon