To the management agent work correctly with Windows Live the MIIS Service Account must be a member of the local administrators group.
If you don't follow this rule you get a stop-extension-dll-exception and in the event log you get:
"System.NullReferenceException: Object.reference not set to an instance of an object"
at
Microsoft.Passport.MIIS_ExtensibleMA.PassportExtensibleMA.WriteLog(String type, String message, String action, String SigninName, string Password, String strNow)"
