I have a customer that wants to know what kind of virus scan software we use on our PCs. The answer is...none. I think they are concerned about network security since these will be on their network. What are the selling points that assure customers these are safe? I know we have a customer who has our PCs on their network and has said he can't ping one of our PCs. He assumed it was a firewall. We have no firewall on our machines. Can you explain why these are safe and why this customer was not able to ping our PC?