Is your ISP blocking outgoing port 25?

Lyndon Nerenberg lyndon at
Thu Jun 18 20:27:40 UTC 2009

On Thu, 2009-06-18 at 16:14 -0400, Joe Provo wrote:
> then you should be shifting your userbase to authenticated on the
> port [587] anyway...

Except for those ISPs who choose to intercept port 587 as well. This is
a big problem with Rogers in Vancouver. They hijack port 587 connections
through some sort of lame proxy that connects you to your intended host,
but strips the AUTH field out of the EHLO response from the remote
submission server ...

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