To prevent infection Mac users should toggle the "Open 'safe' files after downloading" setting whether they're infected or not. It could prevent attacks similar to this one.
- To ensure you do not automatically download the app, uncheck the following: Safari > Preferences > General > uncheck "Open 'safe' files after downloading."
- Searching for the application and deleting it directly may fail, saying the app is in use. To stop it running, check Activity Monitor (in Applications > Utilities) and disable anything that relates to MacDefender.
- Look in /Library/StartupItems and, same place, LaunchAgents and LaunchDaemons for references to the malware app.
- Once quit, head to the Applications folder and drag the MacDefender app to the trash, then delete trash.
- To ensure all references to the app are cleared, run a search using Spotlight and delete all MacDefender references you find.
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