I have configured a postfix server on localhost port 25 to forward email to my ISP's mail server. This allows me to log email in /var/log/mail.log and /var/log/mail.err
I can send diagnostic emails from the two email addresses I have configured just fine and can see these emails in mail.log. Also, I receive emails in response to new tickets on the interface and see these in mail.log
What is not working is the welcome emails and password reset emails. There is nothing at all in mail.log so I doubt its an email configuration issue. osTicket is just not sending the emails.