gotta love the chutzpah of these scammers - they give you a bogus message claiming to be from an AV utility (that you didn't install), but the utility, despite having pinpointed malware on your machine, hasn't quite worked out which flavour of O/S you're running.

well done for not clicking & asking for confirmation of your suspicions., The sad thing is that some % of the computer owning population MUST be clicking on stuff like this, or the scammers wouldn't bother :-(