I need help deleting a quarantined file on Symantec Endpoint Protection for Mac

I got a infected file on May 28th, 2014, which Symantec Endpoint Protection quarantined. I want to delete this infected file from my hard drive. I looked online on how to delete a quarantined file, but I am unable to do it. Firstly, when I go to the quarantine window, there is a lock button at the bottom left corner. When I click it, it does not unlock, so I cannot manage my quarantined files. When I hold the button down, it looks like it is unlocked, but when I let go of the button, it locks itself again. Also, I cannot access the Symantec folder under the Application Support folder because it is not there. Hence, I cannot delete the quarantined file from there either. I was wondering if I need to reinstall Symantec Endpoint Protection on my computer, and if the installation driver that I downloaded will allow me to reinstall the software? Thanks!!