Raise IMAP connections limit per IP


My customers are complaining about a message in Thunderbird saying that it is not possible to connect to the IMAP server because the limit of connections per IP has been reached.

I have been struggling with this for some time now and I have tried:


And set: mail_max_userip_connections = 200

Still having the same issue.

Any ideas?

From the client side, we have also limited the connections per client to 1.

Maybe check your dovecot.log / mainlog for errors.

Maybe try: