Also, merely having an infected data file on a hard drive can't infect a computer - it must be opened. pdf files, data files won't infect a system. I only backup data and, with the exception of Word. it will put your system back to an earlier state that, hopefully, is pre-infection.

What are you backing up? Windows creates restore points for the system, which are a kind of backup, i.e. Firewalls for such machines on such a system are optional (though, of course, if we're talking about laptops that operate in many different environments, the firewall should be turned on). All corporate routers have this, and most home routers do, as well. If it connects via a LAN through a router, the router should be equipped with a firewall and other protection, e.g.

If it connects directly to the internet (not over the LAN through a router), it should have its firewall turned on (Windows OSes have software firewalls built-in). In my view (and I'm not an IT person), every computer on a LAN and/or with internet access should have good anti-malware software. There was a time when IT departments tried to insist that computers be exactly that (and some still do). The safest computer has no connectivity with anything, and which doesn't have USB ports, a CD/DVD drive or a floppy drive, so no one can introduce any code externally. Using computers connected to a LAN, much less the internet, involves a certain amount of compromise between functionality and absolute security. Java is a scripting language - the danger is if someone puts a malicious script on a website. If you do, you'll lose the ability to utilize many websites. I should disable (uninstall?) Java (on all browsers or just Chrome?).

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