Hi,

Just wanted to give everyone a heads-up in the hopes of possibly saving you a lot of time.

I have an smtp server in a data center that I allow all my webhosting clients to use for sending mail. However, Cox home internet blocks port 25, forcing me to use their smtp server.

This is ok except that I have to change my default mail account in Outlook to my companies smtp server when ever I hook-up to a different network outside of my home-office.

So if you have trouble using an smtp server accross the net that you know is working perfect, consider that port 25 may be blocked. I called Cox internet support and had to escalate my ticket to second tier before I got a definitive answer.

Best Regards,

Gene Ballard

You can get your smtp server in the data center to listen on an other port as well as 25 so that you can use that for when you on an ISP that blocks 25, and use the same port for when you are on an ISP that does not block.
Many ISPs block port 25 now-days, Telstra Bigpond here in Australia blocks 25 if you do not have a static IP. I was affected, until I got a static IP for accessing my companies VPN, and port 25 is open now.
I used to have a smtp server listening on ports 25 and 1025 at the office to send via if I was at home (Port 25 blocked) or at the office without changing settings (I used 1025 at both sites, and others used 25 where they were).

It is pretty easy to set this up, and if you have troubles, just post and someone will be able to help.