I've seen weirdness with Outlook where some instances would work on por 587 and some would only work on port 465. So, I would enable both and try both:
Port 465 is the 'smtps' line in master.cf, so I'd uncomment all the lines below:
Code:
smtps inet n - n - - smtpd
-o smtpd_tls_wrappermode=yes -o smtpd_sasl_auth_enable=yes
submission inet n - n - - smtpd
-o smtpd_etrn_restrictions=reject
-o smtpd_enforce_tls=yes -o smtpd_sasl_auth_enable=yes