xfer problems between 2.3.15 and 2.4.17

[gavin.gray at ed.ac.uk]

I have been testing xfer of accounts within a cyrus murder from 2.3.15 
backends to new 2.4.17. backends.

all the email and folders seem to migrate perfectly and the xfer'd 
accounts can send and receive email. However when reading email with an 
IMAP client I am having strange issues setting flags within folders on 
messages. In particular setting and unsetting deletion flags is very 
erratic. In some folders it doesn't work at all, on others I can set the 
deletion flag but can't unset it. All of the backends have delayed 
expunge switched on.

debug output from the alpine IMAP client seems to suggest the server is 
doing what it's told:

IMAP DEBUG 12:04:30 5/7: 01000069 STORE 93 +Flags (\DELETED)
IMAP DEBUG 12:04:30 5/7: 01000069 OK Completed
IMAP DEBUG 12:04:31 5/7: 0100006a STORE 94 +Flags (\DELETED)
IMAP DEBUG 12:04:31 5/7: 0100006a OK Completed

but then something seems to immediately remove the flag, because on 
issuing an expunge the client finds nothing to expunge.

nothing of note seems to be logged on the backend, even logging in debug 
mode.

the other baffling thing is that in some folders within the same users 
account, this whole process works perfectly.

does anyone have any ideas what could be causing this and if there might 
be a solution?

many thanks,

Gavin Gray
Edinburgh University Information Services
Rm 2013 JCMB
Kings Buildings
Edinburgh
EH9 3JZ
UK
tel +44 (0)131 650 5987
email gavin.gray at ed.ac.uk

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