I'm not using port 25. I specifically mention 465 and 587 in the rules and my postconf output verifies this.
By endpoint I mean the public IP address in front of the computer I'm using to send and receive email. Eric Shields 🚏 MassTransitHonchkrow Ask me about the Krowverse Suite of Services. ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On Monday, August 2nd, 2021 at 2:16 PM, Wietse Venema <wie...@porcupine.org> wrote: > Eric Shields | Mass Transit Honchkrow: > > > Hi again. I finally figured out that my firewall rules might be the > > > > reason my connection times out. So when I send an email, it doesn't get > > > > past the SYN_SENT stage of the TCP handshake. In addition, it does not > > > > leave my NAT device. > > ISPs for residential networks often block outbound traffic to TCP > > port 25, which leaves the sending system in the SYN_SENT stage. > > You can test that with netcat (command: nc mail.example.com 25). > > The 'fix' is to send mail through a provider's mail submission > > service on TCP port 587 or 465. > > Wietse
publickey - masstransitkrow@365stops.org - 0x20BE2EA5.asc
Description: application/pgp-keys
