I received an email from one of my readers, Kevin, about using the VSS Driver for Backups. As of 3.5 Update 2 this feature has been introduced. I knew that there was a catch to using the VSS Driver but it seems that many people have overlooked a little detail on page 50 of the documentation of which Kevin was one.
NOTE The VSS component gets installed by default when you do a fresh installation of VMware Tools shipped with ESX Server 3.5 Update 2. If you upgrade from an earlier version, you need to install the VSS component manually.
Please be aware that when you want to use VSS on your existing environment you will need to manually upgrade your version of VMware Tools and select the VSS driver. For Windows 2008 and Vista the VSS driver is not installed by default even when doing a clean install this means that you will need to manually add the driver when VSS based backups is a requirement.