I have two server (Debian 11.3) with Ispconfig 3.2.8p1, and Autoresponder does not work both. We use IMAP, so the email config on server: check Enable receiving and Disable POP3. I try set starrt on end by date too, butdoesnt work. When is see mail.log, all I see is that the email arrives, processes it, and puts it in the mail account. so the email arrives in the account but the sender does not receive out of office notification. We use default email path (/var/vmail), clamav, so nothing special.