Generating user instances in SQL Server is disabled. Use sp_configure 'user instances enabled' to generate user instances

If you are getting the following error:

“Generating user instances in SQL Server is disabled. Use sp_configure 'user instances enabled' to generate user instances” What should I do?

Answer: To fix this, please Open the SQL Server Management Studio Express. This is the downloadable program in the same site where you downloaded the SQL Server 2005 express used to manage SQL Server 2005 Express.

In the query editor type this text: exec sp_configure 'user instances enabled', 1.

Then type: Reconfigure.

Then restart the SQL Server database.

Ref: http://blogs.msdn.com/hongmeig/archive/2007/08/31/generating-user-instances-in-sql-server-is-disabled-use-sp-configure-user-instances-enabled-to-generate-user-instances.aspx