Make sure that your firewall isn’t blocking your mail client’s attempts to connect to the SMTP server.
If this is the case, consult your firewall’s documentation to find out how to let the client go through the firewall.
If the firewall isn’t the problem, then it might be your ISP.
Many ISP’s nowdays block port 25 (the default SMTP port) in an effort to reduce spam. A simple solution is to change the SMTP port in your mail client from 25 to 26. If this doesn’t work, you may need to contact your ISP to find out what you have to do in order to access an outside SMTP server.
If both your firewall and ISP are okay, then the SMTP server might be down. Although we regularly check the status of all our services, you can help us identify and fix the problem faster.
*** Additional Supplemental Information: ***
General Outgoing SMTP Port settings per ISP: (subject to change per ISP)
Comcast is known for blocking ports 25 and 26, their solution is to use Port #587. once you have changed this to port #587, it should resolve the problem.
For more information about comcast’s email settings, see the following links:
For Verizon Fios Customers:
Posted in: EMAIL - FAQ's