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How to host 2 or more domain using Exchange?

Posted on 2009-07-09
Medium Priority
Last Modified: 2012-05-07
I  have seen tons of discussion on this topic, but NO one will explain in detail how to set this up or how to test it. I have spent dozens of hours trying to set this up and it NEVER works.

BOTH on the same physically DB controller with name

WHY is this such a common question and NO ONE can provide straightforward solution, with out going into detail Microsoft talk about forests and trees.

PLEASE DO NOT REFERR ME TO ANOTHER MICROSOFT TECH NET article. Those articles are useless!

I would kill for a simple step by step on how to set this up CORRECTLY!
Question by:NorthwesternTech
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LVL 96

Accepted Solution

Lee W, MVP earned 400 total points
ID: 24818990

Assisted Solution

ahdfx earned 800 total points
ID: 24819002
If you are looking to just adding another domain to the existing users; it is as follows.

Go into Exchange System Manager.
Expand Recipients
Click on Recipient Policies
Double Click on Default Policy
Click on the Tab "E-mail Address (Policy)"
Click on New
Select SMTP Address and click OK
enter "" (you need to include the @)
Make sure the Check box for This Exchange Organization is responsible... is checked and click OK
Place a check in the check box next to the new domain.
Make sure the domain you what as the primary is set. (This will always be the outgoing email domain used.)
Click OK

You can now decide if you want all exchange mailboxes to get the new domain email address.
All new created mailboxes with have both email address.

Let me know if that is what you needed.

Author Comment

ID: 24819129
I have already tried as you suggested.

Now, I create a new user

what are the correct smtp and pop3 server address? is the name of the DC is the new domain

When I go to create a new user it only will allow me to user DOMAIN.COM and not

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LVL 96

Expert Comment

by:Lee W, MVP
ID: 24819288
Please post screen shots.

Are you trying to add a different DNS domain to Active Directory or do you want to simply have Exchange Send and Receive for another domain?  Your question was hosting 2 or more domains using Exchange - in which case, the Petri article I posted answers that.  If you setup your DNS correctly, then your SMTP and POP3 servers are the same as the MX record for the domain.
LVL 76

Assisted Solution

by:Alan Hardisty
Alan Hardisty earned 400 total points
ID: 24819532
If you want to send and receive with multiple domains and multiple user accounts (essentially act as a hosting company), then have a read of my comments in the following question:
These details were extracted from a Microsoft KB Article that was posted on their website, but later withdrawn as it should have been an internal only document, of which I have a copy.

Assisted Solution

ahdfx earned 800 total points
ID: 24819593
what are the correct smtp and pop3 server address?

   The smtp and pop3 have no bearing on the Windows domain name.  That is a DNS issues and you can use what ever you want.

When I go to create a new user it only will allow me to user DOMAIN.COM and not

   All users are created under the "windows domain" name which may or may not be your internet name. In windows Std Server, you can only have a single windows domain, but it can host multiple internet domain names.

What are you trying to do?  After you add a new user, go into AD for users and dbl click on the user and click on the email address tab.  What do you see?  You can add and remove email address there, but only if the recipient policy accepts for that name.

Assisted Solution

GMorineau earned 400 total points
ID: 24828955
a user have one (and only one) account and this account it's managed by active directory. ok?

so you have ONE domain controller and ONE exchange to manage TWO (or more) domains. and the users have one or more emails. But in fact you want your user log in the system or in OWA using your how email. right?

First, create diferents OU, just to make easy to manage your system.
create diferents UPN (in Active Directory Domain and Trust), one for each email and change the User logon in account painel for the user. It will only change the logon way but not the SID or files. The user will also be able to log on OWA using is mail address in "username".

All other configuration like pop, smtp, logon server are the same for all emails domains because all wil look at the same DC.

Author Comment

ID: 25147659
Some of the information is correct and other parts of the information a just wrong or do not work.

After of hours of screwing around, I finally have email from two domains.

domainA and domainB

I can add users and choose:


Each dansmith can actually sent email to each other and it appears they are from different domains.
But dansmith@domainA can see the email of dansmith@domainB. Which is what I was after.

I now have a new problem. The configuration only works if you are on the domain subnet.
LVL 76

Expert Comment

by:Alan Hardisty
ID: 25170094
Time to close this question down and open up another one.  You are more likely to get a better response.  Your original problem has been resolved (from what I have read) and you now have a separate problem.
LVL 76

Expert Comment

by:Alan Hardisty
ID: 25378612
NorthwesternTech - You are clearly quite new to Experts Exchange and for this - it is understandable that you may not know how to best use this site.
The normal process works like this:
You ask a question - an Expert (or more than one Expert) post suggestions as to how to resolve the question you have raised.
Once an Expert has posted a suggestion, it is normal for you to try out that suggestion to see if it works and then provide feedback to the expert who offered the suggestion.
This process repeats until you finally get the answer you were looking for, or sometimes, you get an answer that you were not looking for, but that the answer provided is the solution (e.g., "you cannot do what you want to do" or "that is not possible") and then you close the question down.
You initially responded to some experts suggestions and then completely ignored the other suggestions and did not provide feedback.  Then you posted a message 40 days later saying that you had fixed the problem on your own.
If you want your questions answered correctly - you need to work with the experts to achieve your solution.
From what you have said (now that I have re-read your question and your solution) I could have pointed you to the correct answer if you had come back and told me that what I / others had suggested was not what you wanted.  It seems that you possibly wanted to select an additional domain when creating a new user (nothing to do with email addresses) and this would be achieved by use of the properties of Active Directory Domains and Trusts by adding an additional UPN.

Author Closing Comment

ID: 31601867
No one in this expert exchange really can answer any question correctly.

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