One or more prerequisites for protecting this data source is missing. Ensure that the following prerequisite software is ...

One or more prerequisites for protecting this data source is missing. Ensure that the following prerequisite software is installed on all the nodes in the cluster:  Windows Server 2008 with Knowledge Base article 948465 (http://support.microsoft.com/kb/948465)         AND Knowledge Base article 971394 (http://support.microsoft.com/kb/971394)         - OR - Windows Server 2008 R2 with  Knowledge Base article 975921(http://support.microsoft.com/kb/975921)          AND  Knowledge Base article 975354(http://support.microsoft.com/kb/975354)    If you have already installed the required prerequisite, refresh the agent status in the management tab and try again.