Alert from Norton Anti-Virus - What does it mean?

Offhand, I would say the attempt was blocked if it was a port scan. There is nothing to fix. It was stopped. A port scan is just someone checking to see what ports are open. Sometimes they are used as a back door to sneak into your computer.

Hi cassie, Welcome to Apple discussions.

You can safely ignore messages from Norton Anti-Virus as there are no known viruses that attack OS X. If you have any other Norton than anti-virus, I suggest you uninstall it.



-mj

Offhand, i would say that one of your ports was scanned and Norton blocked it. There are viruses out there that attack Macs, just very few. Malware is supposedly more prevalent. Viruses are more commonly written for PC's. However you can get them in an email and if you forward it to someone on a PC, they get infected.
With viruses, it is better to be safe than sorry. Like taking lots of Vitamin C during flu season.

I wouldn't be concerned about viruses on Macs. If you use an anti-virus program, you should think of doing so as a being a "good neighbor" to Windows-using colleagues (so you do not pass on a tainted emails and files). You won't be affected either way on your Mac.

Other types of malware (not viruses), such as trojans, can be a threat. These pretend to be something else to trick you into running them. Just pay attention to the warnings Mac OS X throws up. If it says program XYZ, which was downloaded from the Internet, is being run for the first time, and you don't know what program XYZ is, don't allow it to run. Or if Mac OS X asks you to give admin user authorization (username and password) at an unexpected time, don't give it.

For Mac OS X, common sense is better than Norton Anti-Virus.

Here's a link to help explain what can hit your Mac.
http://www.macvirus.org/

I repeat, there are NO known viruses that attack OS X.



-mj