Microsoft has for some time produced a Best Practice Analyser (Analyzer for the Americans)
This BPA allows you to review your SBS installation and will highlight any of the common misconfiguration issues that the Microsoft SBS Product Support Team has identified over time. The BPA will download the latest updates for it each time it is run and therefore will always ensure your system is reviewed using current standards.
The BPA is a MUST to be run before you do any type of major works on a system and AFTER you’ve done them too. Also ensure you run it prior to a migration to a higher level of SBS to maximise the chances of success.
You can download the SBS Best Practice Analyser for various versions of SBS from the locations below.