Admins: Can IMAP clients automatically find special folders by SRV records?

Ichinisan

Lifer
Oct 9, 2002
28,298
1,235
136
My employer is a small cable / ISP. We recently had to transition the hosting for the free email accounts our customers use (Google ending the Google Apps for ISPs platform).

Since the transition 1.5 months ago, I've helped dozens of people with issues updating their email configuration on various devices. One common problem: Client devices using IMAP don't automatically detect which special folder to use for certain things.

The correct special folders are:

  • \Drafts
  • \Sent Items
  • \Trash
  • \Spam

I've seen accounts with 4 folders for sent mail (each with slightly different names) because mail clients don't detect the existing Sent Items folder.

Some of the alternate names I encounter:
  • Sent
  • Sent Mail
  • Sent E-Mail
  • Sent Messages
  • Sent Items
  • Deleted
  • Deleted Mail
  • Deleted Items
  • Deleted E-Mail
  • Deleted Messages
  • Bulk
  • Junk
  • Junk E-Mail

Just like SRV records for the domain name can suggest POP/IMAP/encryption settings, is there a way for SRV records to suggest which existing IMAP folders to use for special folders?

It's really tedious to update every single device to point to the correct folders, then merge the contents from the redundant folders, then delete the redundant folders -- and then have to go through everything all over again when the next device is configured. Many users have multiple email addresses. It's tiring...
 
Last edited:

matricks

Member
Nov 19, 2014
194
0
0
Don't know about SRV records, but are you familiar with RFC 6154: IMAP LIST Extension for Special-Use Mailboxes? I haven't been able to find information about client support, but some posts on Dovecot mailing lists indicate Outlook 2013 supports it, which I would take to mean current versions of most IMAP clients support it.

You also depend on server support, Dovecot supports it since 2.1.
 

Ichinisan

Lifer
Oct 9, 2002
28,298
1,235
136
Don't know about SRV records, but are you familiar with RFC 6154: IMAP LIST Extension for Special-Use Mailboxes? I haven't been able to find information about client support, but some posts on Dovecot mailing lists indicate Outlook 2013 supports it, which I would take to mean current versions of most IMAP clients support it.

You also depend on server support, Dovecot supports it since 2.1.

Thank you. I'll pass this along to the right folks.
 

Ichinisan

Lifer
Oct 9, 2002
28,298
1,235
136
Don't know about SRV records, but are you familiar with RFC 6154: IMAP LIST Extension for Special-Use Mailboxes? I haven't been able to find information about client support, but some posts on Dovecot mailing lists indicate Outlook 2013 supports it, which I would take to mean current versions of most IMAP clients support it.

You also depend on server support, Dovecot supports it since 2.1.

The server responds to the "CAPABILITY" command with a string that includes both "LIST-EXTENDED" and "SPECIAL-USE" -- and I believe that implies it has support for RFC6154. However, in my experimentation using the telnet utility, the IMAP server does not report the special flags for any of the special folders (special folders have been set via webmail interface). I've also allowed my iOS 9.3 Mail app to create "Sent Messages" on the server and that folder doesn't show any special flags when I do the IMAP "LIST" command. The only flag I see on any folder is: "\HasNoChildren" (meaning there's no sub-folder, I presume).