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I gave her time to steal my mind away
San Jose, CA
·Pacific Bell - SBC
reply to khockin

Re: Is outbound port 25 blocked/filtered

said by khockin:

Can anyone verify if AT&T Southeast filters outbound port 25?

Specifically I am wondering if you can reach the following 2 IP's on port 25 Port 25 Port 25

I need to verify this for all AT&T regions

Toward the end of 2002 SBC implemented port 25 blocking across their entire 13-state footprint (West, Southwest, Midwest, and Northeast). It was outbound only, and they provided a web site for unblock requests.

At the end of 2005 the SBC purchase of AT&T went into effect. The corporation was re-branded as AT&T. With the assimilation of AT&T Worldnet, port 25 blocking became more difficult to lift.

In 2006 AT&T acquired Bellsouth, which had long blocked port 25, both outbound and inbound, in their 9-state footprint. As all acquired regions were assimilated, the legacy Bellsouth pattern of blocking port 25 bidirectionally became the new standard.

AT&T now blocks port 25 both ways across their entire 22-state footprint (all regions); though up until I canceled service (April, 2011), legacy customers who had requested unblocking (I was one) apparently still had port 25 access. Because of those legacy unblock requests, responses to your query will vary; but if your client is blocked, that is the current default for new AT&T accounts.

I have heard that unblock requests can still be made through AT&T Direct, but I would strongly recommend exploring alternatives.
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum

Bah Humbug
The Boro
·Cingular Wireless
·Comcast Business..
Your port 25 summary is true except that it only applies to residential accounts. Business class accounts are not supposed to have port 25 blocking. The OP appears to be a business class customer since both of the IP addresses point to webmail.attbizclassemail.com (which I would assume from the hostname implies an email site for business class customers).

FWIW, I can get outbound port 25 connectivity to the OP's first IP address ( from the two AT&T business class connections to which I just established a VPN tunnel (as well as from my normal Comcast Busineess Class connection).

OTOH, the OP's second IP address ( does not respond to port 25 requests at all It does respond to port 110, which tells me that it is probably a POP3 server only, and does not have SMTP capabilities.
We can never have enough of nature.
We need to witness our own limits transgressed, and some life pasturing freely where we never wander.