Tuesday, May 03, 2005

One way to "send as" when using multiple domains

If you remember a while back, I made a series of blog posts on how to How to Host Multiple Domains on SBS 2003. Since that day, many people have asked how you can send mail as a specific user@domain.com, when the user has accounts in multiple domains.

I asked a few of my Exchange guru buddies around here, and I got an answer that I thought I'd share with you (later rather than never). I haven't tried these out yet (hey, it was the choice of testing this, or giving you SP1... :) )

Here they are, from the horses mouth!

  1. Create a mail-enabled group (aka Distribution List) representing each one of the incoming addresses. The primary SMTP address (that is the upper-case SMTP type address that you see in Active Directory Users and Computers) should reflect the correct inbound domain. So, for example, you can create the following groups with the associated SMTP address:

    • Group 1 - SMTP: Mailbox1@domainA.com

    • Group 2 - SMTP: Mailbox2@domainA.com

    • Group 3 - SMTP: Mailbox1@domainB.com

    • Group 4 - SMTP: Mailbox1@domainC.com

  2. So, hopefully you can see what I'm doing here ...the inbound mail destined for a specific mailbox and domain actually resolves to a group rather than an actual mailbox. From here, you can just add whichever mailboxes you like to the group, and of course, those users will receive the mail via the group.

  3. The next step is to allow your users "send as" permissions on each group object (you do this through Active Directory Users and Computers as well). So, when a user replies to a mail, then can use the optional FROM: box in Outlook to pecificy/choose the name of the group that they want the message to be from.

  4. When your user sends the reply, the message is stamped as coming from the group e-mail address, which of course will have the correct domain name stamped on it (this comes from that upper-case SMTP type address).

Good luck, let me know if there is something that needs changing and I'll update it so we have the most accurate information here.


Anonymous said...

Great stuff, i remember needing a solution for this a while ago and not finding anything, except a third party app that didnt work very well.

Ive just tried it on our exchange 2000, and it works fine.

Maybe exchange will integrate this feature more conveinently one day...

Anonymous said...

I seem to be having some difficulties though... I cannot see how to set the "Send As" permissions on the Distribution Group. I CAN see where to do it on the Users to whom I want to give Send As permission but in there I cannot see the Distribution Group! Please help

Sean Daniel said...

This is most likely a property of the group, and not available in the default Wizard. Try going into the distribution groups snap-in and right clicking and choosing the properties.

Anonymous said...

I am a little confused about these steps, is there a step-by-step procedure written down anywhere? I am attempting to implement this on a 2000 exchange with 2000 outlook. Please reply.

Sean Daniel said...

Hrm, this is unfortunately for Exchange server 2003.

Unknown said...

Oufff, I also need a step by step to done this sucessfully..

Thanks for your help

Anonymous said...

Hey Sean-

Good stuff! I need to implement this for a client running SBS 2008 Premium. Do you know if I'll need to remove all external addresses from the user accounts before assigning the address to the mail-enabled group? (I plan on creating 3 mail-enabled groups per user account)

Sean Daniel said...

I don't think it matters, but whomever replies to the mail to the group, it will go out from that domain name.

Mark McDonald said...

Here are the steps I took to get this working with SBS 2008.

Go to this link if you want to know how to setup SBS for multiple domains.

1. Add the group using the SBS Group wizard (be thought full with this name as it will be used as the email name when the email is sent)
2. Open the Exchange Console from the start menu
3. Click Recipient Configuration and double click to edit your newly created group.
4. Click Email addresses and add the email address for the new domain. Remove the check mark for automatically update policy. And click "Set as Reply"
5. You need to now grant "send-as" rights to the end user(s). Right click the "exchange management shell" from the start menu and select runas administrator.
6. run the following command with your sepecific options:

Add-ADPermission "YourGroupHere" -User "EndUserHere" -ExtendedRights send-as

That was it! Now - be sure your secondary domain is setup and working before attempting these steps.