I have a local server which host PHP applications. My applications send emails to different addresses. However, I am noticing a problem that I am unable to figure out. It send emails to internal addresses but it won't send messages to external addresses.
I also have an exchange server on the same network. so for example I have these 2 "internal domain"
domain1.com domain2.com
if I execute this php function from my application it gets delivered with no problem
mail("name@domain1.com","Test Subject","Test message");
However, if I try sening a message to gmail, yahoo or any external domain it does not send it
mail("name@gmail.com","Test Subject","Test message");
My server is running on Windows 2008 Server R2 with PHP5.3.19 installed on it via IIS6
How Can I correct this issue?