Client can receive e-mails from outside and inside of our domain, with no problem. But, I cannot send e-mails to outside of our domain.(external network). Sending e-mail internally is fine. Every time a try to send to an outside address I have the following.

WARNING: delayed mail. <<< Connection refused

I have one server acting as our mail-relay. Our three mail server is point to this mail-relay server. I am adding courier as another imap mail server to use our mail-relay server as well. On the mail-relay log file, I had problem with starttls, looking for a cert. I disabel this feauter o courier, and now, nothing shows on the mail-relay log and the error message sending outside e-mail still the same. Sorry my english. any help? --Alex