Hi Guys

I hope you dont mind me jumping on this thread.

I am having some issues with TLS and SMTP. Basically if in Postfix "mynetworks" I set some networks I have no problems with the server starting "STARTTLS" and exchanging certificates etc, however when I have clients that route through a "protected" POP environment I cannot get the server to STARTTLS from the client. Now my inkling has been that some ports in the POP must be causing some issue, however from traces at the client and general reading TLS seems to ride on port 25.

"blacky_5251" I note you mention that 'Outlook needs to use port 465 for sending emails..' are you sure TLS uses port 465??

I will be getting traces from the POP but any solid info on this would help me.

Regards

Your question is totally separate from what was being asked in the thread you posted, so I've moved it into a new thread of its own.

The change I made to master.cf is to tell Postfix to listen on port 465 as well as 25. I was successfully using port 25 and TLS with Thunderbird, but I needed to open port 465 for Outlook with different authentication rules - specifically removing noplaintext from the smtpd_sasl_security_options - because Outlook will only work with SSL - not TLS. SSL likes to use plaintext, which isn't a problem really because the link is encrypted anyway.