How to get rid of a virus on an infected Mac computer, and protect your Mac from getting infected again

Hollis Johnson/Business InsiderYou can get rid of a virus on a Mac computer with a few different methods.

  • There are several steps you can take to get rid of a virus on an infected Mac computer and get it back up to speed.
  • If you’ve identified which programs on your Mac are malicious, you can use the Activity Monitor to check for and remove any malware that may be active.
  • Stopping a virus altogether involves searching your Mac pretty thoroughly to ensure all traces of the virus are gone.
  • You should use malware-scanning software to help identify and eliminate viruses.
  • Visit Business Insider’s homepage for more stories.

We all know the signs: Sudden reboots. Frozen screens. Pop-ups that just won’t stop. Mysterious extensions showing up in your browser.

Getting a virus on your Mac is never fun, especially when it starts interfering with your computer’s performance.

But there are ways to stop it in its tracks and get rid of it. And, perhaps best of all, those methods are free.

To help identify malicious programs, you should consider first using malware-detection software like Clean My Mac X or Malwearbytes to scan your computer.

Once you’ve identified likely sources of infection, there are a few ways you could go about manually removing programs or extensions to help get your Mac back up to speed.

Check out the products used in this article:

MacBook Air (From $US1,199 at Apple)

How to get rid of a virus on a Mac

Stop malicious programs from running on your Mac

1. Go to your Launchpad (the rocket ship icon in your bottom toolbar).

2. Search for the activity monitor and click to open it. It may be located by default in a folder labelled “Other.”

1 GET RID VIRUS MACDevon Delfino/Business InsiderFind and open Activity Monitor.

3. If you know which programs are malicious, find them in the CPU tab of your activity monitor and stop them from running by clicking the ‘x’ in the top-left area of the window.

2 GET RID VIRUS MACDevon Delfino/Business InsiderFind and stop programs that are harming your computer.

Uninstall bad apps

1. Open your Finder.

2. Toggle over to “Applications.”

3 GET RID VIRUS MACDevon Delfino/Business InsiderYou can drag programs straight from your Applications folder to the Trash.

3. Look for any apps you don’t recognise, or any that have exhibited malicious behaviour (e.g. opening unprompted and unexpectedly).

4. Drag any such apps to the Trash icon (located in the bottom toolbar of your screen).

5. Empty the trash by clicking on the icon and selecting “Empty” (located in the top-right corner of the window).

Get rid of any virus-related browser extensions

Safari

1. Launch the browser.

2. In the top toolbar, click “Safari” and then “Safari Extensions.”

5 GET RID VIRUS MACDevon Delfino/Business InsiderOpen the ‘Safari Extensions’ menu.

3. Look for suspicious extensions and uninstall those.

Chrome

1. Launch the browser.

2. Click the three stacked dots in the top-right corner of the screen.

3. Hover over “More Tools” and then click “Extensions.”

4. Look through your extensions and “Remove” any you don’t recognise.

Firefox

1. Launch the browser.

2. In the top-right corner, click the three vertical lines and choose “Add Ons.”

3. Toggle over to the extensions tab and get rid of any that you aren’t familiar with.

You may also want to change your browser’s homepage and search engine preferences if the virus has impacted those areas.

Get rid of login items you didn’t opt for

This is another area where viruses can hide within your Mac. Here’s how to find yours and get rid of any extra ones:

1. Click the Apple icon in the top-left corner of the screen and then select “System Preferences.”

7 GET RID VIRUS MACDevon Delfino/Business InsiderOpen your System Preferences.

2. Tap “Users & Groups” and toggle over to “Login Items.”

8 GET RID VIRUS MACDevon Delfino/Business InsiderYou can pick and choose which programs open at startup.

3. Untick the box next to any login items that you don’t recognise.

Other steps you can take to get rid of a virus on a Mac

  • Even if you go through all of the above steps, it’s still a good idea to once again run a malware-detection software like Clean My Mac X or Malwearbytes – both are free and will give you peace of mind when it comes to your computer’s health.
  • If you’re still worried about having a virus, you may want to create a new user profile on your Mac. Many viruses are user-specific, rather than device-specific.
  • For those who use Time Machine, one other thing to consider is restoring an old version of your computer to wipe out all traces of the virus. It’s relatively quick and easy, but you’ll lose any changes that have been made since the last backup.
  • And, as a last resort (or for those who have access to Apple’s technical support), calling in a professional can be a good idea.

How to avoid getting another virus on your Mac

Be sure to look out for virus-friendly websites and files, and avoid them by doing things like leaving spam emails unopened and only downloading from trusted, known sources

Installing a security system on your Mac is also a good idea to prevent malware from infecting your computer in the future. Another positive step to take is keeping your Mac updated, so that new software patches can be applied, leaving your computer less vulnerable to bad characters.

And, as always, be sure to back up your Mac so that, even in the event of a virus, your data and media are protected.

Related coverage from How To Do Everything: Tech:

Business Insider Emails & Alerts

Site highlights each day to your inbox.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.