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How to run a Mac virus scanner


Macs don’t get viruses, right? Wrong, sadly. Your Mac may be safer from malware than the average Windows PC, thanks to its Unix core and Apple’s default security settings in the OS, but it’s not immune. All it takes is one thoughtless click on a link in an email or on a website, and your Mac could be infected.

The good news is that performing a Mac virus scan is very easy and if it finds anything, getting rid of the virus is very straightforward, too. 

How to check your Mac for a virus

There are a number of tell-tale signs that your Mac has a virus. If it’s not displaying any of those, there’s probably nothing to worry about. So, before you scan your Mac for a virus, here are a few things to check.

1. Is your Mac behaving erratically?

This could include applications crashing, web browsers loading pages you didn’t ask for, and unusually high traffic on your network. 

2. Has it started running very slowly all of a sudden?

Some viruses run processes that hog CPU cycles and leave little capacity for the tasks you want to carry out.

3. Are you seeing adverts or pop-ups for things you would never normally see?

Adware viruses are designed specifically to show adverts in the hope that you’ll click on them.

4. Have you noticed software appear on your Mac that you didn’t deliberately install?

Some viruses appear in the form of browser extensions, others run in the background, but some may appear as applications in your Applications folder.

If any of the above are true, it’s possible that your Mac has a virus, but don’t panic, it may be relatively easy to remove.

How to get rid of suspicious apps

If you find an application that you didn’t intend to install, you should get rid of it. But don’t just drag it from your Applications folder to the Trash, that won’t remove every trace of it from your Mac. Applications store files in a number of different places in your Mac’s Library folders. You could hunt them down and remove them manually, but it’s quicker and easier to use a dedicated uninstaller like CleanMyMac 3. That way, you can be sure you will remove every trace of the application and no stray files will be left behind.

  1. Download CleanMyMac for free here.
  2. Launch it from your Applications folder.
  3. In the Utilities section, click on Uninstaller.
  4. Look through the list of applications until you see the one you want to get rid of.
  5. Check the box next to it.
  6. Press the Uninstall button.


CleanMyMac also makes it easier to uninstall browser extensions. To see what extensions it has found for Safari and Chrome, click on Extensions in the Utilities section and then click either Chrome Extensions or Safari Extensions. If you spot an extension you didn’t intend to install, check the box next to it and press Remove.

Free virus scan for Mac

If you haven’t found any applications or browser extensions you didn’t intentionally install, or if your Mac is still showing signs of having a virus after you install them, it’s time to do a full virus scan.

Don’t worry, it’s not as difficult or as expensive as it sounds. In fact, there are several Mac virus scanners that allow you to scan for free. However, it’s very important that you don’t just Google ‘free Mac antivirus software.’ Many sites that claim to offer free antivirus tools in fact host viruses themselves. So, you go to the site looking for a solution and end up making the problem worse. It’s important to use a reputable antivirus tool. Here are some reputable Mac antivirus tools:

• Avast Free Mac Security
• AVG Antivirus for Mac
• BitDefender Antivirus for Mac
• Kaspersky Internet Security for Mac
• Intego Mac Premium Bundle X9

They’re not all free, but most will allow to at least scan your Mac for free.

Once you’ve checked out the apps above and chosen one, download it and install it, following the developer’s instructions. Once it’s installed, launch it from your Applications folder and follow the guide on screen to run a virus scan.

Most antivirus tools allow you to run scans on an adhoc basis but will also allow you to schedule them to run at regular intervals, so you can be sure you haven’t downloaded a virus. They’re updated regularly with details of new malware, so it’s important that when an antivirus tool alerts you that there’s an update available, that you download it immediately. That way you’ll be sure that your Mac is being scanned for the latest viruses.

How to prevent your Mac from getting a virus

Prevention is always better than cure. So, if you want to make sure that every virus scan returns a clean bill of health, here’s what to do.

  1. Never click a link in an email unless you’re 100% sure where the email has come from and where the link will take you. Reputable companies and banks won’t ask you to click a link to log into an account, for example.
  2. Never download anything unless you’re certain what it is. That includes movie files, software updates, games, and anything else you’re not absolutely certain about.
  3. Keep your Mac updated with the latest version of macOS. That doesn’t mean you have to be running the very latest OS, but if you’re running, say, Sierra, make sure you install the latest updates when they become available.

Scanning your Mac for a virus is very easy. There are several very good antivirus tools available and some of them are completely free. Before you download one, however, it’s worth checking your Applications folder in case you’ve unwittingly downloaded a virus that’s now sitting there. Also, check your browser extensions. CleanMyMac can help you get rid of any applications or browser extensions you didn’t intend to download, and it’s very quick and easy. Give it a go.

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