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isp port blocking

Posted: 2004-07-16 18:22
by nwkit
what can be done if my isp is blocking ports?

after a few changes in ports..i can send out...but still, i cannot receive any emails..

is there osmething i can do to bypass my isp blocking?

Posted: 2004-07-16 18:47
by mcampbell
If this is a consumer personal use ISP then you're probably screwed though you can try asking them. If you have a dynamic IP though (Even with dynDNS or other 3rd parties like it) it probably won'y work because the port would be open for one IP but shut for the next IP you get.

If this is a business class use ISP then tell them to open the port or you'll move to someone else.
I get the feeling though (and remembering your previous posts) that you are in the first category.

Posted: 2004-07-16 18:52
by nwkit was working well for several months until my stupid isp decides to block some ports....

21, 25, 80, 110

Posted: 2004-07-16 18:55
by martin
If your incoming port 25 is blocked and you can't open it, the only way around it is to find someone to act as a gateway for you.

In hMailServer 3.3, it will be possible to set up such a configuration. ServerA accept emails for your domains and forwards them to your ServerB on for example port 1025. That will ofcourse require a ServerA placed somewhere on the net. Perhaps you can find someone who can't send on port 25. Then you could act as a gateway for outgoing mail for him and he could act as an incoming for you. =)

Posted: 2004-07-16 18:56
by mcampbell
FTP, Web and Mail. Looks like the don't want anyone doing anything.

Posted: 2004-07-16 18:57
by tm
There are some SMTP Redirection Services available that will work round the blocked ports... not ideal but it will get you up and running again.

here's one:

Posted: 2004-07-16 19:53
by nwkit
thanks for replying so quickly..

i have 2 choices i guess..

1) change isp to one that has buisness dsl with server support on static...
2) get another service that bypasses the port 25 blocking

if i do choice do i get my domain to point to my server? what do i do with the DNS do i set up different additions to my domain (eg.,, etc)

Posted: 2004-07-16 20:04
by martin
That depends entierly on what DNS software you are using. If you have a fixed IP adress you can use the free service on to setup your domain/subdomains and connect them to your IP address.

Posted: 2004-07-16 20:20
by mcampbell
I may be misunderstanding here but if you want your domain to point to your server (or any server that is a valid host for said domain) you would change the Name Server records for you domain via your registars website. (,, etc)

If you are talking about pointing your Mail servers domain name,, then yes you can use (which I acually use for one of our company sites)
If you are going to be hosting your mailserver via your own static IP as given to you by an ISP, don't forget to also request that the ISP setup a reverse lookup on their end for your domains mail server.
IE: when a reverse lookup is done on it should return [satic-IP] PTR

Posted: 2004-07-16 23:49
by polarunion
nwk check out the info i wrote on dns over at the site.. lots of info on it and lots to get you back and online again. I say grab another ISP. that's rediculous especially if they've changed their terms of service right in the middle of your contract. I feel for ya.*what a headache*

Posted: 2004-07-17 07:59
by nwkit
it's not really change of's just the terms never stated no server...but by word of mouth from tech support..they say no im' not surprised that they finally started some port blocking...

but yah...switch of isps soon maybe...

Posted: 2004-07-19 15:51
by mcampbell
Hey if it's not in the TOS then I say tell them to unblock it until they have "No Servers" in writing and more specificly what they mean by a server because we all know there are many different types. (Mail, Web, Application, DB, RAS, FTP, File, Storage...etc etc)
That should at least buy you a little time, probably not much depending on how big they are and if they have a lawyer in house.

Posted: 2004-07-19 18:14
by nwkit
they are pretty big i guess...they cover telephone/mobility/internet for 2 provinces...

but im' using a temporary measure right now..and will change as soon as my contract ends for one thing

Posted: 2004-07-20 07:47
by polarunion
what province are you in? i'll give you the downlow on the good ones for canada...

Posted: 2004-07-20 22:55
by nwkit