Error Detail: A system error prevented the service pack from installing. Please download and run the “Check for System Update Readiness” tool at http://go.microsoft.com/fwlink/?linkid=122602.
If the “Check for System Update Readiness” tool doesn’t fix the problem, visit the Microsoft website for more information.
Resolution: If you face above error then download and run the System Update Readiness tool from http://support.microsoft.com/kb/947366/.
More details: http://support.microsoft.com/kb/947366/ - Error message when you try to install the stand-alone package for Windows Vista Service Pack 1 or Service Pack 2 or for Windows Server 2008 Service Pack 2: "Installation was not successful" or "An internal error occurred while installing the service pack"