|It's always a good idea to run a router firewall, that denies the most unwanted traffic or connection attempts.|
It's also another good idea to run a firewall on every desktop pc behind this router.
This firewall should include an application firewall so that you will be asked whether a new program should be allowed to start and what kind of network traffic is allowed for that program.
So a download routine, you may get via email will not be started automatically without your knowledge, and it's not automatically allowed to download other viruses or trojans to infect your system.
Please send a reply, if you solved the problem !!!