dovecot version: 2.3.9.2

When I use dsync:

/usr/bin/dsync -v -D -o plugin/quota= -f -u my@email.dom backup maildir:/tmp/mailbackup/Maildir

it always stops when it comes to a folder with an "@" in its name.

Error Message:

Warning: Mailbox changes caused a desync. You may want to run dsync again: Remote lost mailbox GUID (maybe it was just deleted?)

I dont know if it makes a difference, but my dovecot uses mdbox and the backup export is maildir.

Hans