What's this?... ip68-5-3-157.oc.oc.cox.net Attack Name: Portscan

Are you running Norton Security? Looks like a notification that it detected and blocked a portscan from the outside world. You probably could have clicked on "Learn more about this attack" to ... learn more.

A portscan is a detection method to see what network vulnerabilities you have. Think of it like a burglar trying the doors and windows. Generally this only tends to be a problem if you have a computer hooked directly into the internet and don't have a firewall or other protection. Adding a wired or wireless router between your computer and your modem can help protect against incursions.

If you're not running Norton, and it just appeared while you were browsing, it's a spam popup designed to scare Windows users into downloading malware, and you can just close the window and ignore it.

Matt