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You don't need any antivirus, because OS X has got its own security systems as XProtect or Gatekeeper that keeps your Mac safe. If you want more information about OS X and malware, see > http://www.thesafemac.com/mmg
Apart from that, please not install MacKeeper or any commercial antivirus > https://discussions.apple.com/docs/DOC-3036
Julio Boim Esteves wrote:
I would like to have some help in order to decide for an antivirus for my Mac: Norton, MacKeeper; ...
Can you help me?
I can't recommend either of the two. Pretty sure MacKeeper will do more harm to your Mac than some malware. Norton is Windows AV... not sure I'd want a repackaged version of their windows product on my Mac. But if you do, then go with Norton. Otherwise, I recommend taking a look at Intego: http://www.intego.com/intego-built-for-mac