We have a ASA5510-CSC10-K9 w/the plus license. We have 3 sites. The main site has an Exchange 2007 server. The other sites use SMTP w/authorization to send mail to Exchange. Mail from users at the other 2 outside sites to internal (company) users is delivered without issue. However, when these users try to send mail outside of the domain (to gmail.com for instance), they get a "550 5.7.1 Unale to relay" error message. When we turn off the SMTP protocol under the "Service Policy Rules" that sends traffic to the CSC, the mail goes through successfully. Any ideas? I can't find any relay configuration under Trend (CSC).