The other day I downloaded some software off the net. With the source looking a little suspect I scanned the files with three engines. GData AV (BitDefender & Avast) returned clear for the files, Kaspersky online also returned clear. Prevx Edge was also running but did not come back with any problems. Although it seems that all the tests have passed, this doesn't mean to say that there wasn't any malware installed, just that it wasn't detected or unknown. Lets say there was 0day malware in this application, how can I check this out for myself?