Page 2 of 2

PostPosted: Mon Oct 01, 2007 6:28 pm
by MrGamma
It would seem this blocking is only for people running a mail server behind the ISP's network...

Anyone simply logging in to check their pop3 account would be unaffected... Someone please correct me if I'm wrong as I find it very hard to believe that ISP's would block the default mail port that is set during a new outlook express email account setup...

Rather stupid considering we must all send and receive email... this port 25 block must be for mail server blocking only...

anyone have details about this?

PostPosted: Fri Nov 30, 2007 3:19 pm
by kevin
Hi,

This is for everyone including end users, not limited to mail servers.

We have 1-2 questions a day about this issue and it's quickly resolved by changing the email client's smtp port to 26.

You can test and see if they are blocking port 25 by opening a dos window in Windows and typing:

Code: Select all
telnet mail.yourdomain.com 25


Replace yourdomain.com with your actual domain name.

If you see a blank screen then your ISP is blocking that port.

------------------
Kevin

PostPosted: Thu Jan 10, 2008 3:57 pm
by tony
MrGamma wrote:It would seem this blocking is only for people running a mail server behind the ISP's network...

Anyone simply logging in to check their pop3 account would be unaffected... Someone please correct me if I'm wrong as I find it very hard to believe that ISP's would block the default mail port that is set during a new outlook express email account setup...

Rather stupid considering we must all send and receive email... this port 25 block must be for mail server blocking only...

anyone have details about this?


It is not blocking a mail server behind your ISP. This is a block to all 3rd party SMTP servers by a customer of the ISP.

They block all outgoing SMTP traffic on port 25 to external servers in an attempt to stop spam. You will only be able to send on port 25 to your ISP's Mail server.

Re: SMTP PORT 25 BLOCKED: I can receive but can not send email.

PostPosted: Wed Feb 09, 2011 12:30 pm
by Feldon
First, what can I do if I'm trying to connect to the server cwh11.canadianwebhosting.com over SSL on port 465? This is being blocked. Switching to port 26 means giving up the secure connection.

Second, using my ISP's SMTP server is just a work around, and means I can't have a properly formed SPF record, and since the average ISP isn't offering SSL, it means giving up the secure connection.

Third, changing to port 26 is just a workaround. Eventually the ISP's will catch on (if they haven't already).

I would suggest its time for Canadian Web Hosting to either stop offering e-mail or get on the Authenticated Email bandwagon. I'm feeling like I'm going to have to switch hosting providers to get proper email set-up.