Solved

Client change email port to 2525, now we can't send to them....How can we now?

Posted on 2007-04-11
8
240 Views
Last Modified: 2010-03-06
Hi,

We have a small client who uses an ISP for their email services.  One day they decided to change the mail port from 25 to 2525 to try to stop spam.  Well, since they've done this many folks (Us included) have been unable to send to them.  We just figured this out by chance and then called the client to verify.  Telnetting to port 25 of the server yields nothing now since their ISP is now blocking that.  Now, the question is how can I configure our Exchange 2003 server to send email to this particular domain over port 2525 without causing issues with the thousands of others we send to?

TIA

Al
0
Comment
Question by:alchik
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
8 Comments
 
LVL 31

Accepted Solution

by:
LeeDerbyshire earned 125 total points
ID: 18890182
You can change the port number in Exchange System Manager by looking at the properties of the Default SMTP Virtual Server, and clicking the Advanced button.  That will allow you to send to this one client, but when everyone else is using port 25, you won't be able to send to anyone else.  The rest of the world assumes that SMTP servers listen on port 25 - they can't keep trying every port to discover the changed port number.  If they can't connect on port 25 they will just give up.
0
 
LVL 104

Expert Comment

by:Sembee
ID: 18890230
The client needs to change their port back to 25. They cannot expect everyone who emails them to use another port. Asking Hotmail, AOL or any other major ISP to comply will be met with a polite no at best and a laugh at worst.

You cannot deal with spam by simply changing the port.

Simon.
0
 
LVL 1

Author Comment

by:alchik
ID: 18892168
The client has no control over the ISP changing the port unfortunately.  After doing some googling it seems others are doing this as well.  I was sort of hoping there was a way of routing domain specific traffic to say, a specific connector/virtual server what would send out via 2525.  
They say there are receiving email from some people.  I can send to them from gmail and yahoo.
0
Are your AD admin tools letting you down?

Managing Active Directory can get complicated.  Often, the native tools for managing AD are just not up to the task.  The largest Active Directory installations in the world have relied on one tool to manage their day-to-day administration tasks: Hyena. Start your trial today.

 
LVL 104

Assisted Solution

by:Sembee
Sembee earned 125 total points
ID: 18893389
I cannot believe that the ISP is expecting this to be a public facing port. As Lee has stated above - the entire SMTP system is based on the port 25. Like http is port 80, https is 443 and POP3 is 110.
This sounds like either a massive cock up by the ISP or someone has taken the private port (for client to ISP communication) and is treating it as the public facing port.

Simon.
0
 
LVL 1

Author Comment

by:alchik
ID: 18897854
I agree with you Sembee.  I've emailed their ISP support group directly (funny, their mail server works just fine...) to see if I can get an answer.  The client has tried to get an answer from them but the ISP claims it's everyone else's fault.  It's bizarre but seems it's not an isolated incident.  Dyndns.com offers MailHop to get around such things.  Odd....
0
 
LVL 104

Expert Comment

by:Sembee
ID: 18897917
The service that dyndns.com is offering is a private service. You send your email to them and then they send it on to the internet using the conventional ports. I suspect this is a similar service.

Simon.
0

Featured Post

Has Powershell sent you back into the Stone Age?

If managing Active Directory using Windows Powershell® is making you feel like you stepped back in time, you are not alone.  For nearly 20 years, AD admins around the world have used one tool for day-to-day AD management: Hyena. Discover why.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Check out this step-by-step guide for using the newly updated Experts Exchange mobile app—released on May 30.
Sometimes clients can lose connectivity with the Lotus Notes Domino Server, but there's not always an obvious answer as to why it happens.   Read this article to follow one of the first experiences I had with Lotus Notes on a client's machine, my…
Internet Business Fax to Email Made Easy - With eFax Corporate (http://www.enterprise.efax.com), you'll receive a dedicated online fax number, which is used the same way as a typical analog fax number. You'll receive secure faxes in your email, fr…
A short tutorial showing how to set up an email signature in Outlook on the Web (previously known as OWA). For free email signatures designs, visit https://www.mail-signatures.com/articles/signature-templates/?sts=6651 If you want to manage em…

691 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question