When installing System Centre Operations Manager 2012 and you are pointing to a remote Data Warehouse (for example, one shared between distributed management groups in a central location) which is behind a firewall, you may see the following error:
"The installed version of SQL Server is not supported. Verify that the computer and installed version of SQL Server meet the minimum requirements for installation. Please see the Supported Configurations document for further information"
After checking that you ARE using a support SQL version (for reference, the supported list for SCOM 2012 SP1 is: Microsoft SQL Server: SQL Server SQL 2008 R2 SP1, SQL Server 2008 R2 SP2, SQL Server 2012, SQL Server 2012 SP1) take a look in the installation logs (Logs are located in the %LocalAppData%\SCOM\Logs directory for the account under which installation was run.)
The chances are you've probably got an error trying to get the remote OS version or an RPC error. This is because the installation requires more than just port 1433 open to the remote DW to run additional tests against the database and SQL service.
It took me a while to run through this with our security team (thanks Lyudmil!) but this should be the list of ports you need to get your installation working in this scenario:
tcp 1433, tcp 135, udp 137, tcp 445, tcp 49160, tcp 60224
I hope that saves someone a bit of pain :)