Don’t click that pop-up!
If you get a popup or re-directed web page on your Mac that says anything about having a virus, or needing to download a free virus scanner, don’t do it. These are deceitful tricks – it is impossible for any website to magically see that your Mac has a virus. That said, if you have downloaded anything called MacDefender, MacProtector, or MacSecurity, these are the malware and are not legitimate programs. It’s easy to take care of, and Apple will have a software update shortly that will clean it off any machine that has it, as well as help protect you from getting it in the future.
There is no emergency, and no you should not run out and buy Anti-virus software for your Mac. Below is a link to information from Apple about how to check your computer, just in case. Of course if you have any questions or concerns, you know how to get a hold of us!