Yes, both client and server support IMAP MOVE, and both also support CONDSTORE.
I have tried both with and without CONDSTORE enabled in the client, with the same result. I am very confident IMAP MOVE is actually being invoked, because intra-account moves occur extremely rapidly. (much faster than inter-account moves, which of course is a copy & delete) Thanks so far. Client is Postbox & Thunderbird on Windows. (I realise Postbox is based on Thunderbird) Greg. On 4 August 2014 22:03, Reindl Harald <h.rei...@thelounge.net> wrote: > > > Am 04.08.2014 um 14:00 schrieb Timo Sirainen: > > On 04 Aug 2014, at 10:44, Greg Sullivan <greg.sulli...@sullivang.net> > wrote: > > > >> I would like to use a shared IMAP account, with multiple users > accessing it > >> simultaneously. The users would take ownership of messages by first > >> attempting to MOVE the messages from the Inbox, into their private IMAP > >> folder, still within the same account. Now, since there will be multiple > >> users competing for the same messages, I naturally want only ONE of the > >> simultaneous moves to be successful at a time. > >> > >> So far, this isn't working. If I do the move from two clients, > >> simultaneously, the messages can go to *both *destination folders - > >> duplicates can result. > >> > >> Is it possible to configure Dovecot and/or an IMAP client to behave the > way > >> I want it to? If the answer to this is YES, then I'll offer my config > >> details. If the answer is NO, the next question is - do any email > systems > >> at all behave the way I want? (I tried a hosted Exchange/OWA service - > it > >> has the same problem) > > > > Dovecot doesn't even attempt to do atomic MOVEs. I don't think any > server will. If you can change the client code, you could use CONDSTORE > instead, which does give atomic STOREs. > > Internet Message Access Protocol (IMAP) - MOVE Extension > http://tools.ietf.org/html/rfc6851 > > well, both, client and server would need to support it > rely on that is unlikely for many years > >