I'd suggest you open up a case with support to get to the bottom of this issue as there are multiple reason why this can happen. It may have to do with the authorization (not authentication) of the particular user ID used. Perhpas it can no longer see certain areas of the host because it doesn't have sufficent rights anymore. Thus, it can't run that specific check which would cause the descripency in the detection date. This is just one reason why this may happen.
You might an authentication report or check the Information Gathered (blue) QID results in the scan and look for authorization issues. Regardless, support will be able to help you drive this to resolution.
Thanks for the quick response..
As mentioned above there are machines with authorization successfully but till last detection date is 17th Mar 2014 and few with authorization failed on servers in the last detection dates is 17th Mar 2014.
What i think is that may be the vunerability got patched.
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