Is your ISP blocking outgoing port 25?

Christopher Morrow morrowc.lists at
Thu Jun 18 21:01:01 UTC 2009

On Thu, Jun 18, 2009 at 4:27 PM, Lyndon Nerenberg<lyndon at> wrote:
> 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

port 26 FTW!

in all seriousness, most isp's (consumer provider folk) today do some
form of blocking of port 25, if you are 'smart' enough to evade this
sort of thing, then you can still do email/blah. 99.999% of users are:
1) not interested in bypassing it
2) not clued into what's going on
3) using webmail

Why is this debate still ongoing??


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