Is your ISP blocking outgoing port 25?

Paul M Moriarty pmm at
Fri Jun 19 21:52:56 UTC 2009

>> AT&T is the major one that I know of that is still enforcing this  
>> policy.
>> But they said they can unblock port 25 upon request. I am not sure  
>> how easy
>> it is.
> It's trivial. A web form. You get the link when you try to send mail  
> to port 25 anywhere else. At least with Yahoo/SBC dsl.
> I got the business class DSL from AT&T and no such nonsense exists.

Same here with U-Verse and a /29 of static IP's.  No blocking since  
Day 1.

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