Installing SCCM 2012 Secondary Site using A Pre-Installed SQL Express 2008 R2 Instance

This is a very helpful article on pre-installing SQL Express on a SCCM 2012 Secondary server so you can customize the install to fit your needs.

http://blog.tyang.org/2012/04/09/installing-sccm-2012-rtm-secondary-site-using-a-pre-installed-sql-express-2008-r2-instance/

Even after all of the tweaking noted in the article I still had issues.
I ran into these errors logged in \\CM12-Primary\%systemDrive%\ConfigMgrSetup.log

-CSql Error: Cannot find type data, cannot get a connection.
-*** [08001][17][Microsoft][ODBC SQL Server Driver][DBNETLIB]SQL Server does not exist or access denied

However, even after enabling TCP/IP and setting the port to 1433 I still could not connect.

• I then validated that SQL Browser was running, but didn’t help.
• I used netstat -a to validate that TCP 1433 was listening and UDP 1434 shows as *:*.
• I could connect to SQL locally using SQL Server Management Studio and SQLCMD, but I could not remotely UNTIL I added the port to the connection string (CM12-Secondary\CONFIGMGRSEC,1433).

It turns out that I didn’t set an exclusion in my SCCM Servers Firewall GPO for SQL Browser (UDP 1434). After adding the exclusion and running GPUpdate all is well.