I'm convinced now that Kas is the best around. Several Times on machines that I have been brought into the shop or I went to service and has had viruses and Avg, Nod 32, Norton, McAfee, or TrendMiicro have not been able to get rid of I have installed Kas and it has taken care of the problem. It may take a while to scan but it does a thorough job and gets it done. to Kas.