Is your ISP blocking outgoing port 25?

Jeroen Wunnink jeroen at easyhosting.nl
Fri Jun 19 09:28:55 UTC 2009


Yes..

1. Customers remember it more easily
2. Some ISP's also block 587 (hence 'SMTP ports' rather then 'SMTP port' 
in my previous comment ;-)


Patrick W. Gilmore wrote:
>
>
> Sent from my iPhone, please excuse any errors.
>
>
> On Jun 19, 2009, at 8:53, Jeroen Wunnink <jeroen at easyhosting.nl> wrote:
>
>> We just open port 2525 for customers from ISP's blocking official 
>> SMTP ports so they can use their dedicated servers/domain mailservers.
>
> Is there any reason you do not use port 587, SUBMIT?
>
> -- TTFN,
> patrick
>
>
>> Lyndon Nerenberg wrote:
>>> On Thu, 2009-06-18 at 16:14 -0400, Joe Provo wrote:
>>>
>>>> then you should be shifting your userbase to authenticated on the
>>>> SUBMIT 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 ...
>>>
>>>
>>>
>>
>> -- 
>>
>> Met vriendelijke groet,
>>
>> Jeroen Wunnink,
>> EasyHosting B.V. Systeembeheerder
>> systeembeheer at easyhosting.nl
>>
>> telefoon:+31 (035) 6285455              Postbus 48
>> fax: +31 (035) 6838242                  3755 ZG Eemnes
>>
>> http://www.easyhosting.nl
>> http://www.easycolocate.nl
>>
>>
>>
>

-- 

Met vriendelijke groet,

Jeroen Wunnink,
EasyHosting B.V. Systeembeheerder
systeembeheer at easyhosting.nl

telefoon:+31 (035) 6285455              Postbus 48
fax: +31 (035) 6838242                  3755 ZG Eemnes

http://www.easyhosting.nl
http://www.easycolocate.nl






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