[Exim] cannot mail to external domains

I am new at this and setting up exim to prevent external relaying but it now seems to prevent
mail from our internal IP addresses to any external host. I cannot mail to anyone but a local
users in our domain. Error message: The mail server responded: host does not relay mail;
relaying to (foo@???) prohibited by administrator. Please check the
message recipients and try again.

What am I missing?
thanks!
-jm