"bdn---" == bdn--- via dovecot <dovecot@dovecot.org> writes:
my program sends messages via Dovecot + Postfix .
No, your program sends email via postfix listening on port 25 or 487. dovecot doesn't send email, it receives it and then lets an MUA manipulate it.
Sometimes it can try to send more than 300 messages at one time.
How is your program doing the submission?
The result is a message: Error working with IMAP . Error code: 9 Server response: Logged In
Are you trying to save an email into the "Sent" folder?
What could it be? a limitation? what? and I don't see any specifics in the logs
You need to share more details and give more context before we can
really help you. Postfix should be able ot handle many many many more
emails than 300, but maybe you don't mean messages, but recipients?
Are you sending a message to mroe than 300 people at once?
But again, the details matter, so please let us know more of what you're doing.
John