How to delete quarantined files?

Hi all,

 

I have searched these forums but could not find an answer to my question.

 

I have the latest version of NIS and in this screen (see below) several items (1) are listed which have been put in quarantain.

 

 

How do I delete these items permantly ? Button (2) is to used to delete the history, but instead of deleting the history I want to delete this quarrantined files.

 

Any suggestions on how to do that ?