hi i have dovecot 2.0.9 - the version from rhel6 - and the following setup: two imap-servers with distinct /var/indices. those directory is local only, no sharing. the users mailboxes life on a shared nfs-storage. the two servers are setup active/passive: only one server is active and in case of a problem or maintenance the second server jumps in. no director in place. we would like to upgrade to rhel7 and add a director. there would be dovecot 2.2.10, but will take some time. one application (horde + activesync which use imap to access emails) seems to have troubles during the second server being active. horde relies according to their deveolpers heavily on modseq/qresync and if we switch to the seconds side there is another set of index-files. my knowledge was that deletion/corruption of index-files would be never a problem, as dovecot recreates them automatically. is this true for QRESNC, too? * is it a problem to have a old set of index-files on the second server, as this system is only in use every 3-4 weeks? * would it be better to start with empty indices? but there we have trouble with horde. and as it seems only with horde. "normal" imap-clients seem to be fine. yours josef