Hey Matt,
It sounds like you might need to do a couple of things.
- Make sure that port 25 is open on that IP.
- Make sure that port 25 is selected for that IP in Settings->Bindings->ports
If both of these things are true you can try rebooting the server to reset the NIC.
Please let me know if this helps.
Kind Regards,
Zach Sylvester
System/Network Administrator
SmarterTools Inc.
(877) 357-6278
www.smartertools.com