The SMTP set up form suggests ports 25, 465, 587 but this doesn’t seem to be working.
Port 25. Your server is sending an invalid domain name of “pd0mdwk001BPF”. Can you update this to be a valid domain, as this is getting rejected?
2026-09-15T14:37:23Z DEBUG SMTP connection started (smtp.connection-start) listenerId = “smtp”, localPort = 25, remoteIp = xxx.xxx.xxx.xxx, remotePort = 6016
2026-09-15T14:37:23Z INFO Invalid EHLO command (smtp.invalid-ehlo) listenerId = “smtp”, localPort = 25, remoteIp = xxx.xxx.xxx.xxx, remotePort = 6016, domain = “pd0mdwk001BPF”
2026-09-15T14:37:23Z DEBUG SMTP connection ended (smtp.connection-end) listenerId = “smtp”, localPort = 25, remoteIp = xxx.xxx.xxx.xxx, remotePort = 6016, elapsed = 57ms
Port 465 is reserved for implicit TLS. I tried selecting port 465 with STARTTLS ticked or unticked. There is no attempt to connect on port 465. Is there a missing button for “Implicit TLS” or is port 465 access not really possible? (if so, best to remove it from the example ports).
Can you please let me know about the above? I don’t have a listener on port 587 at the moment and Quickfile would be the only thing using it. It’s best practice to favour Implicit TLS on port 465 over STARTTLS on 587.
Thank you
Hi @smithdrp
I will relay this to our development team who would be able to advise on this better than I would.
However, a few notes is that we don’t do anything special with the SMTP connection, we just attempt the connection based on the details you provide. We have many users using 25, 465 and 587 with various settings and SMTP servers.
Who is your SMTP provider? I’m happy to take a look and see if we can find some settings that do work for other users?
Hi Mathew,
I’m using a basic Stalwart configuration but even trying to reconfigure back onto an older Postfix/Dovecote config is not working for me now.
Hi @smithdrp
Nothing has changed on our side regarding this so if your older setup worked, this should continue to work now, too. If you have the SMTP server you can share, I can check if we have any other users using the same server and advise on some alternatives to try.
There’s nothing special with our SMTP connection - it takes the details you enter, and creates a connection.
What’s really weird is that it works - even though the page says SMTP settings have been deactivated. Can you let me know what the developers said about how to configure port 465 for implicit TLS please? And why does it show an error if sending is working?
Please provide the requested details.