2011: How to install SQL Express on a domain controller

Autodesk Vault Server is unable to install Microsoft SQL 2008 Express on a domain controller due to the account used to run SQL services. This is a new restriction Microsoft has placed on Microsoft SQL 2008. For security reasons, Microsoft recommends that you do not install SQL Server 2008 on a domain controller. SQL Server Setup will not block installation on a computer that is a domain controller, but the following limitations apply http://msdn.microsoft.com/en-us/library/ms143506.aspx

• On Windows Server 2003, SQL Server services can run under a domain account or a local system account.
• You cannot run SQL Server services on a domain controller under a local service account or a network service account.
• SQL Server Setup cannot create security groups or provision SQL Server service accounts on a read-only domain controller. In this scenario, Setup will fail.

Use the following procedure to configure the new SQL instance.

1. Create a new user account that will run the SQL services. (2010 Advanced Configuration Guide Page 46)
2. Install  Microsoft SQL using the Advanced Configuration Guide and specify the account created in the previous step. (2010 Advanced Configuration Guide Page 19)

Advanced Configuration Guide