Should I install Norton anti-virus on my Mac El Capitan?

FranNewForest wrote:

Should I install Norton Premium on my Mac,

Please don't install any such protection software on a Mac. It is unnecessary.

FranNewForest wrote:

is Mac existing protection/security/Firewall good enough? Don't wish to compromise my Mac if the built in protection is the best to use.

Yes, the built in protection is good enough.

Keep OS X and all other applications updated.

For more info:

http://www.apple.com/osx/what-is/security/

Hi,

Regarding Norton. No. Viruses, Trojans, Malware - and other aspects of Internet Security

Going by your profile your Mac has El Capitan installed which includes System Integrity Protection > About System Integrity Protection on your Mac - Apple Support

Please read Phony "tech support" / "ransomware" popups and web pages.

On a Mac, those things are a mere annoyance. "Zepto" only affects Windows PCs.

Do not install non-Apple "anti-virus" products on a Mac. Please read Effective defenses against malware and other threats.

If you already installed "Norton" on your Mac, it won't run properly. Uninstall it. One or more of the following may be applicable:

Uninstall Norton Internet Security for Mac

Removing Symantec programs for Macintosh by using the RemoveSymantecMacFiles removal utility

RemoveSymantecMacFiles