sending email problem

[John B. Smith]

I started getting some kind of 'certificate expired' objections when I
tried to send email to my ISP (Spectrum). For no reason I tried "use
subission port (537)" and apparently it will work that way. What did I
do?

[Ajo Wissink]

Post by John B. Smith
I started getting some kind of 'certificate expired' objections when I
tried to send email to my ISP (Spectrum). For no reason I tried "use
subission port (537)" and apparently it will work that way. What did I
do?

Submission port 587 works because it is the required port for outgoing
mail.

[Grant Taylor]

Post by John B. Smith
I started getting some kind of 'certificate expired' objections when
I tried to send email to my ISP (Spectrum). For no reason I tried "use
subission port (537)" and apparently it will work that way. What did I do?

Were you using the SMTPS port (465)?

Did you also tell your client to use STARTTLS on the Submission port
(587)? If you didn't tell it to use STARTTLS, chances are good that
you're not activating TLS encryption on the Submission port (587) and
thus not seeing the error for the expired certificate. (This assumes
that both ports are hosted by the same server & same certificate.)