May 13 13:28:17 dsync(
saywhatnow@letest.tld): Debug: brain M: Local mailbox tree: INBOX guid=980aa92b41a37e62cd0f0000537c03e1 uid_validity=1652466497
May 13 13:28:17 dsync(
saywhatnow@letest.tld): Debug: brain S: Local mailbox tree: INBOX.INBOX guid=00000000000000000000000000000000 uid_validity=0
So your remote has INBOX and INBOX.INBOX. This is quite special case for imapc connector and cannot be solved easily. I did hit this once at a customer when I was doing migrations for them.
This was few years a go and unfortunately I cannot remember how the problem was solved. I remember that it required TWO separate dsync runs to migrate INBOX separately and remaining folders in another run.
I wrote a workaround to the migration framework to monitor the migration logs and then apply workarounds if end user and this strange INBOX.INBOX setup.
Unfortunately that is all I can remember about it and I've since left Open Xchange and do not have an access to my old migration toolkit bits and command line documentations.
Sami