Install Exchange 2010 without 64bit DCs

No 64bit Domain Controllers in Forest Root Domain


Recently a customer wanted Exchange 2010 installed into a multi domain environment where the forest root domain had no 64 bit servers. As the Exchange 2010 setup program will only run on a 64 bit machine you will need either a 64bit DC or 64bit member server in the forest root domain to run the necessary preparation routines.


This can easily be addressed but it requires some thought beforehand - ie, don't get caught out by bad planning and have to rush the procedure through change control!


Basically the machine that you use to prepare the Active Directory must be in the same domain and site as the schema master and if it is not a domain controller it will need the RSAT (Remote Server Admin Tools) installed.


According to Technet topic article - 

Forest/Domain Preparation - With Exchange Server 2010, you will need to leverage a 64-bit operating system to perform the schema extension and forest/domain preparation work. Hopefully you have 64-bit Active Directory servers deployed (or are planning to deploy them) and this won't be an issue. In the event that you do not have 64-bit Active Directory servers, you can install a 64-bit member server (physical or virtual) into the forest root domain, place it in the schema master's AD site, and apply the schema and forest preparations; for domain preparation, you can either update all domains by leveraging the /preparealldomains setup switch, or by removing/joining the 64-bit member server to each domain in the forest that you need to update.

When Exchange 2010 is installed into an organisation with more than one domain the setup process needs to make certain changes to the directory schema and AD structure. This process is normally handled seamlessly by the Exchange setup program and if you have only one domain then regardless of the DCs in use the Exchange 2010 server must be a 64 bit machine so assuming it is in the same AD site as the schema master your setup will proceed directly from the new exchange server itself.


If your forest root domain does not have any suitable 64bit DCs I have found the easiest thing to do is to move a potential exchange 2010 server into the Forest Root domain (ensuring it is in the same site as the schema master), run the exchange setup program as follows:

1. Move suitable server into Root Domain
2. Open Powershell as Administrator
3. Import-Module ServerManager - to allow you to add windows features
4. Add-WindowsFeature RSAT (& restart) If you don't do this setup will fail

Once you have got the server ready we need to use an elevated command prompt and use the Exchange 2010 CLI setup program to prepare the Schema, Exchange2010 permissions and AD itself. See http://technet.microsoft.com/en-us/library/bb125224.aspx for the full explanation.

So, from the command line we need to run the following commands:

setup /prepareAD This command prepare AD as a whole (sub features like legacy permissions are automatically prepared)

setup /pad This will prepare ALL domains in the forest

Once you have taken these steps you should check to ensure that the relevant security groups etc have been created in both the top level and child domains. Assuming they have you can proceed to move the 64 bit server back out of the root domain and continue to install exchange 2010 into the organisation.