I have setup an exchange server for a company. Internal mail works correctly and mail can be received from the outside world. I am using Cablevision for business and port 25 is open both ways. I have my mx record setup and pointing to my external ip address. Why can I not send mail to the outside? My internal domain is setup as company.int..... and my mail server points to the internal dns server (DC). Could that be the prob? DO I have to change something in my internal DNS? I really need to get this working ASAP so any help is much appreciated.