In my misguided attempt to protect my Mac from the possibility of unknown malware, I tried to install and implement FileDefense. I never actually had the chance to examine this program. It crashed my Mac on installation. (Ever since the advent of OSX, I can count on one hand the number of times I have had to restart my Mac due to a crash.) It crashed again on its initial activation and it crashed one more time on subsequent restart. In fact, I had to make a firewire connection from my laptop to my desktop, bring up the latter's hard disk and then remove FileDefense. Fortunately, after the offending software was excised, my desktop once again worked flawlessly. If you do not have access to a second Mac before you install this software, don't even try.