On 7. May 2025, at 13.38, Markus Bach via dovecot <dovecot@dovecot.org> wrote:
I think I finally found out what's going wrong.
The problem seems to be that the shared mailbox uses more storage space than the users limit. It looks like dovecot is comparing shared_mailbox.usage + message.size with user.limit.
This was already posted on this mailing list 11 years ago: https://dovecot.dovecot.narkive.com/NMG8xbaD/quota-using-wrong-limits-in-use...
At least I think it's the same problem because after increasing the users quota they were able to save the message. I don't really know why saving worked when we first looked at the issue. It wasn't when I tried today.
Would be good to test if it's fixed in v2.4 releases, since there have been quite a lot of changes. Or if not, it might be logging more debug output with log_debug=category=debug