We have two different Active Directory domains on the same LAN. Domain1.com Domain2.com We have one smtp email domain, that is user@Domain1.com We have one Exchange cluster, that is on Domain1.com Users in Domain2.com want to start using our exchange server, & have the same email user@Domain1.com for all users. Any suggestions to allow this to happen? I did some research that involves setting up a domain trust. If a domain trust is needed, then here is the info... Domain1.com is at Windows 2003 level w/ Windows 2003 DNS servers. Domain2.com is at Windows 2000 level w/ Windows 2000 DNS servers. Thanks, Jason

Which version of Exchange? A trust would be involved, but just for authentication. The WINDOWS domain has nothing to do with the email domain, so the fact that the users want to receive email on the same EMAIL domain is fine. This is just a matter of authentication and mailbox configuration, but version of Exchange is key - I suspect 2003. Simon. Simon Butler, Exchange MVP Blog | Exchange Resources | In the UK? Hire Me.

Sorry, its Exchange 2007; in a CCR cluster. JasonJason Lehman

Also, the two domains are not in the same forest. Thanks,Jason Lehman

On Wed, 22 Aug 2012 15:58:32 +0000, JasonLehman wrote: >We have two different Active Directory domains on the same LAN. >Domain1.com > >Domain2.com Domains or Forests? It's significant! If it's two different Forests then do both of them have their own Exchange organization? If the 2nd AD Forest doesn't have an Exchange organization then you can use them as a "resource" Forest and create accounts for them in your "account" forest. >We have one smtp email domain, that is user@Domain1.com > >We have one Exchange cluster, that is on Domain1.com > >Users in Domain2.com want to start using our exchange server, & have the same email user@Domain1.com for all users. > >Any suggestions to allow this to happen? I did some research that involves setting up a domain trust. > >If a domain trust is needed, then here is the info... > >Domain1.com is at Windows 2003 level w/ Windows 2003 DNS servers. > >Domain2.com is at Windows 2000 level w/ Windows 2000 DNS servers. > >Thanks, > >Jason --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

On Wed, 22 Aug 2012 15:58:32 +0000, JasonLehman wrote: >We have two different Active Directory domains on the same LAN. >Domain1.com > >Domain2.com Domains or Forests? It's significant! If it's two different Forests then do both of them have their own Exchange organization? If the 2nd AD Forest doesn't have an Exchange organization then you can use them as a "resource" Forest and create accounts for them in your "account" forest. >We have one smtp email domain, that is user@Domain1.com > >We have one Exchange cluster, that is on Domain1.com > >Users in Domain2.com want to start using our exchange server, & have the same email user@Domain1.com for all users. > >Any suggestions to allow this to happen? I did some research that involves setting up a domain trust. > >If a domain trust is needed, then here is the info... > >Domain1.com is at Windows 2003 level w/ Windows 2003 DNS servers. > >Domain2.com is at Windows 2000 level w/ Windows 2000 DNS servers. > >Thanks, > >Jason --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP

Hello Jason, If these domains are in the different forests, and you want users in Domain2.com can use Exchange server in Domain1.com, I suggest you use linked mailbox to do that: How to Deploy Exchange 2007 in an Exchange Resource Forest Topology http://technet.microsoft.com/en-us/library/aa998031(v=exchg.80).aspx How to Create a Linked Mailbox http://technet.microsoft.com/en-us/library/bb123524(v=exchg.80).aspx Thanks, Evan Liu TechNet Subscriber Supportin forum If you have any feedback on our support, please contact tngfb@microsoft.com Evan Liu TechNet Community Support

Hello Jason, If these domains are in the different forests, and you want users in Domain2.com can use Exchange server in Domain1.com, I suggest you use linked mailbox to do that: How to Deploy Exchange 2007 in an Exchange Resource Forest Topology http://technet.microsoft.com/en-us/library/aa998031(v=exchg.80).aspx How to Create a Linked Mailbox http://technet.microsoft.com/en-us/library/bb123524(v=exchg.80).aspx Thanks, Evan Liu TechNet Subscriber Supportin forum If you have any feedback on our support, please contact tngfb@microsoft.com Evan Liu TechNet Community Support

Hi Jason, Any updates on this issue? Thanks, Evan Liu TechNet Subscriber Supportin forum If you have any feedback on our support, please contacttngfb@microsoft.comEvan Liu TechNet Community Support

Yes, sorry. I had to wait for our network admin to setup the proper access between the two VLANs. I am going to attempt to setup the domain trust now & then try the linked mailbox approach. For now Exchange will be in Domain1.com only. Thanks,Jason Lehman

I think everything will be easy after you setup the domain trust. Thanks, Evan Liu TechNet Subscriber Supportin forum If you have any feedback on our support, please contacttngfb@microsoft.comEvan Liu TechNet Community Support

I just got back from being on vacation all of last week. Sorry for no updates. The domain trust was setup successfully. I was able to create a linked mailbox per your suggestion. Here is where I am having a problem... When a user from Domain2.com logs onto their pc, we seem to be having authentication issues w/ the Exchange server. From Outlook 2007, we get the first time Outlook 2007 Startup wizard. We get a message saying "An encrypted connection to your mailserver is not available. Click Next to attempt using an unencrypted connection." So I went back a few steps in the wizard & chose to manually configure server settings. I get to the screen where it asks for the name of your Exchange server. I put in the fully qualified domain name. Then type in the user name, then click the Check Name button. Here is where I get prompted for a user name & password; that I can't get passed. Any suggestions of what user name & pw should work there? Should it be the user that is logged in from Domain2.com OR the disabled account that got created when I setup the linked mailbox? Thanks, Jason Lehman

I got it working, but want to better understand the setting I changed to make it work. It was an Authentication setting in the domain trust that I setup. In the properties of the domain trust, there is a tab called Authentication. There are two choices. 1. Domain-wide authentication 2. Selective Authentication I originally had Selective Authentication selected as it sounded the most secure; just to let the users in domain2.com use are Exchange resources. As soon as I changed this setting to Domain-wide authentication; in domain2.com; the prompts in the Outlook 2007 clients went away & the users mailbox's now opened. Now my questions are... 1. What exactly did I just open/enable by selecting the Domain-wide Authentication? 2. Is there a documented procedure to go back to the Selective Authentication & allow domain2.com to only access the Exchange resources from domain1.com? ThanksJason Lehman

I got it working, but want to better understand the setting I changed to make it work. It was an Authentication setting in the domain trust that I setup. In the properties of the domain trust, there is a tab called Authentication. There are two choices. 1. Domain-wide authentication 2. Selective Authentication I originally had Selective Authentication selected as it sounded the most secure; just to let the users in domain2.com use are Exchange resources. As soon as I changed this setting to Domain-wide authentication; in domain2.com; the prompts in the Outlook 2007 clients went away & the users mailbox's now opened. Now my questions are... 1. What exactly did I just open/enable by selecting the Domain-wide Authentication? 2. Is there a documented procedure to go back to the Selective Authentication & allow domain2.com to only access the Exchange resources from domain1.com? ThanksJason Lehman