Hi, I'm looking for a solution to install Exchange 2003 after I've ran the Exchange 2007 setup and therefore also the schema extensions for Exchange 2007. Before I tried to install Exchange 2003, I followed the instructions in the following TechNet article: http://technet.microsoft.com/en-us/library/aa998313(EXCHG.80).aspx However (asI suspected) thisdid not work as planned and I got an error while installing the 'Microsoft Exchange Messaging and Collaboration services' compontent from Exchange 2003. After searching this errorI found the following TechNet article which describes the exact error I'm getting: http://support.microsoft.com/kb/937051 The article explains the problem but there is no sollution mentioned. The problem seems to be that a certain containerdoes not exist (CN=Active Directory Connections) and this container is normally created by the forestprep from the Exchange 2003 setup. However the article states that it I should not run this forestprep... CanI create this container manually by ADSI Edit or do I need to roll back the schema extension from the Exchange 2007 setup?Any help is appriciated Thanks in advance, Steve.

Hi According to following article, after you deploy a new Exchange 2007 organization, you can't add servers that are running earlier versions of Exchange to the organization. The addition of earlier versions of Exchange to Exchange 2007-only organization is not supported. Coexisting with Exchange Server 2003 and Exchange 2000 Server http://technet.microsoft.com/en-us/library/aa998604.aspx I think that you can perform the following method to get the Exchange 2003 installed. Nevertheless, please understand that it is not a recommended method as the KB indicated. I suggest you create a separate forest for Exchange 2003 and upgrade it to Exchange 2007. 1. Completely remove (uninstall) the Exchange 2007 out of the organization. The last Exchange 2007 uninstall should remove the traces of Exchange organization out of active directory. 2. Run Exchange Server 2003 Setup /forestprep and /domainprep. Then, reinstall the Exchange 2003 server 3. Rejoin the Exchange 2007 into the organization You can also refer to the following thread: http://forums.microsoft.com/TechNet/ShowPost.aspx?PostID=3630252&SiteID=17 Mike

Mike, Thanks for your response... I've decided not to go trough with the Exchange 2003 installation and will be installing Exchange 2007 as initially planned. I've removed the Exchange 2003 'traces' from AD with ADSIEdit and setting up my 2007 organization... Grtz, Steve.