[MlMt] Preserving tags

[Bill Cole]

On 12 Feb 2018, at 18:16, Rick Holzgrafe wrote:

> Is there any way to preserve not just the mail, but also the tags that 
> we have applied in Mailmate? I have explored the Application Support > 
> Mailmate folder, but as far as I can tell the tag info is not stored 
> there, except for a handy list of all the tag names.

The tags are stored on the server as IMAP "keywords" a.k.a. "flags."

This is a standard part of the IMAP protocol, but support for 
user-defined keywords/flags is sparse. MacOS X Server uses Dovecot as 
its IMAP server and so supports an arbitrary collection of keywords. 
Many email service providers (e.g. Microsoft) have IMAP keyword support 
so limited that it might as well not exist. Others (e.g. Google) 
conflate flags/keywords and folder names, so massive weirdness can 
occur.

BOTTOM LINE: You cannot count on a mailbox storage & access provider to 
support existing MailMate tags. If they use Dovecot, Cyrus, or Courier, 
you may be able to just drag messages across and let MM do the work. 
Otherwise? Who knows.

POSSIBLE SOLUTION: It's fairly simple to yank the mailboxes out of the 
MacOS X Server mailstore and drop them into a MacPorts (or Homebrew or 
handmade) installation of Dovecot.