actually Rob, if one has been updating their OS all along, n need t install virus protection. Also, viruses written for PC's as this one obviously was does not affect Macs. The conclusion therefore is that one is far less likely to have your computer infected by a Mac
Whether those abilities are present in the version of OS X that you are running will likely depend on how old your Mac is and whether you’ve been upgrading the operating system along the way (if you haven’t, you really should you know) – malware detection was introduced with OS X 10.6 (Snow Leopard).
It operates in a way that many of you will know to be very similar to the antivirus programs that Windows users rely upon so heavily, quarantining content downloaded from the internet, using Code Signing certificates to verify the legitimacy of that content, and regularly downloading security updates that refresh a database of known threats targeting the Mac’s operating system.
Whenever you attempt to open files downloaded by a quarantine-aware application (some examples of which are Safari, Messages and Mail), you will be presented with a dialog box which will remind you what you are opening, where you downloaded it from, and at what time. If everything checks out you can continue to open it, otherwise you can cancel it.
Should you try and open a file that is known to be malicious, OS X from Snow Leopard onward will interrupt you with an alert box which will remind you what file you are trying to open, where you downloaded it from and at what time, along with a description of the issue it presents.
If the alert says the file is malware and will damage your computer you should, of course, move it to trash or, if it is a disk image, eject it.
Assuming you pay heed to those warnings and don’t open malicious files your Mac should stay virus free.
http://www.pcadvisor.co.uk/how-to/se...ained-3418367/
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