Remove Mac Defender and variants

Do you get the pop-up when using a browser?

Safari – Popup takes over

Safari – Popup takes over (2)

Popup remover – Scam Zapper

If the pop-up reloads, force quit Safari (command - option/alt - esc) and reopen with the shift key held down. If that doesn't work, disconnect from the Internet, go to Safari/History and delete the website. Quit and reopen with the shift key held down.

Are you thinking of something else, such as MacKeeper? Can you provide a screenshot of the message?

Make a screenshot by following the directions here:

http://support.apple.com/kb/HT5775

Attach the screenshot file, which will be found on the desktop, to a reply to this message.

Sorta related: Don't upgrade your OS if you have malware issues as they'll probably start multiply with something like Sierra. And also I've been told that malwarebytes is all you need.. totally false. My malwarebytes/computer is hacked so it claims it scans all my files in 1 second which is obviously impossible. Also its a total scam because as far as I know it only checks for the 70 or so "known" Mac specific malware signatures that your computer probably already has in it's extremely limited capability to check for. Malwarebytes found no issues on my computer with all sorts of corrupt junk.

Please see these brief mentions of security vulnerabilities patched with every single OS update if you live in the real world: https://support.apple.com/en-us/HT207797

But please don't let me stop anyone from removing circa 2009 malware using Malwarebytes. Sure there are some nasty adware programs out there advertising Thor Pro-Virus (available in the Mac App Store for just $9.99!).

Download this program which was written by Thomas Reed, a long time poster. The program will do the work for you which makes it easy.

Malwarebytes Anti-Malware for Mac 10.9 and later

What should I do if Malwarebytes Anti-Malware for Mac didn't solve my problem?

What makes you believe that you are infected with MacDefender? MacDefender was last seen in 2011, and is currently extinct, so you cannot possibly have gotten a new MacDefender infection.

What specific behavior are you seeing that concerns you?

Ahh, that is very different than MacDefender.

Malware Crusher is a junk app by a company (PCVARK) whose sole business model relies on scamming people out of money using their junk apps. As macjack says, Malwarebytes will detect and remove that.

Pretty much everything you said is completely wrong.

Upgrading the OS is not going to cause problems with malware spreading. In fact, since upgrades are one of the times that Apple's built-in Malware Removal Tool runs, it may actually solve some problems.

I'm not sure where you get the idea that Malwarebytes only checks for "70 or so" things, but that is completely false. As the person primarily responsible for maintaining the rules used by Malwarebytes for Mac, I can attest to that.

Antivirus Thor is a scam. There are multiple issues with it that I'm not going to go into here, but suffice it to say that I ran a bunch of real-world Mac malware and adware past it and none of it was detected. (But it did falsely detect some Linux malware that was not actually present.)

How to avoid or remove Mac Defender malware in Mac OS X v10.6 or earlier - Apple Support

MalwareBytes should remove it.