***What could happen if I install the KN for windows XP on server 2008 R2, though this is not a Symantec question ***
That patch not installed saying some platform error or not required.
Same error received you ca run manually windows update.
ScriptGen: ShowServiceProgress() Look for timeout starting SepMasterService or other failure loading SIS.dll.
http://www.symantec.com/business/support/index?page=content&id=TECH217284