Cybersecurity in personal devices is a rising concern, and mitigating the risks of malware is essential to all users of digital devices. When we talk about your phone or laptop becoming infected by malware and viruses, we often suggest a factory reset of your device. But you may be wondering if a factory reset removes a virus. So, let’s delve into this topic.
What happens when you perform a factory reset?
Does a factory reset remove malware? To answer that question, we first need to understand what a factory reset is and what happens when you do one.
A factory reset completely wipes all of the contents of your iPhone or MacBook and puts everything back the way it was when it first rolled out of the factory. In other words, the result is a completely clean device with freshly reinstalled apps. By wiping everything, a factory reset will remove all viruses and malware from the device.
In the past, returning your Mac to fresh-out-of-the-box condition was a long, drawn-out process. But with newer Macs, a factory reset is much quicker and painless.
Can a factory reset get rid of malware from your device?
Will a factory reset erase everything? No, unfortunately, you can’t count on a factory reset to remove all malware.
A factory reset will eliminate most malware. Garden-variety threats like trojans, spyware, or adware will be cleansed from your machine. But other types of malware can be more deeply rooted. If, for example, you have malware in the firmware or rootkit of your MacBook, a factory reset probably won’t remove it.
Firmware- or rootkit-level malware usually resides deep inside the operating system. They can be in the boot process or within modified firmware. It is entirely possible that the malware was even preinstalled by a hacker who then sold the laptop to you. You could also be the target of a government (in which case, it might be quicker and safer to smash the laptop and walk away).
Be careful who you purchase a MacBook from. You never know what is hiding in it. Macs can get viruses, despite what Apple enthusiasts will insist on telling you.
Before we move on, keep in mind that MacBooks are notoriously locked down, making it difficult to access the deepest parts of the system. If you have firmware or rootkit malware on your MacBook, it may take a certified Apple Genius to remove it.
Will a factory reset eliminate hackers from my device?
A factory reset will remove any malware and system changes that a hacker made on your device, essentially reversing their damage. However, the method they used to gain access to your device may remain a threat.
If, for example, a hacker took advantage of a Mac vulnerability or installed a rogue app, then that will be fixed with a factory reset. But if they gained access through a weakness in your network, a factory reset of your device isn’t going to fix the problem. The malware may be removed, but further action will need to be taken to ensure that the incident isn’t repeated.
How to factory reset your Mac to remove a virus
As we just mentioned, the Mac factory resetting process has become much easier on modern Macs. So, if you think it’s the best option to ensure the safety of your device, it may be worth it.
First, make sure you disable Find My and FileVault on the Mac or MacBook. Also ensure that you have the activation codes for any software you want to reinstall after the rest is complete.
A word of caution: If you aren’t sure where the virus or malware came from, you may be better off restoring your Mac from a backup. And be careful about which files you plan to reinstall manually. You don’t want to inadvertently put a virus back onto your freshly reset computer.
To factory reset your Mac, simply do the following:
- Go to System Settings > General > Transfer or Reset.
- Click Erase all Contents and Settings.
After you enter your administrator password, the Mac will begin the process of wiping itself. Make a cup of coffee and wait.
Once the process has finished, do not restore from iCloud unless you know for sure when the virus entered your machine and you have a backup dated before that time.
How can you reset your iPhone to remove a virus?
Resetting your iPhone is also a quick and easy process. The same caveats apply — disable Find My, don’t restore it from a backup, and be cautious about what files you choose to reinstall.
To factory reset your iPhone, simply do the following:
- Go to Settings > General > Transfer or Reset iPhone.
- Select Reset. Do not select Erase all Contents and Settings. (That does not do a full reset of the phone.)
- Tap Reset All Settings.
- Enter your iPhone PIN and let the phone do the rest.
Factory Reset Assistant failed? Here’s how to manually factory reset your Mac
If you want to easily and quickly reset your Mac, you can use the built-in Factory Reset Assistant. However, there are several scenarios in which this tool might not work.
Here are some cases when Factory Reset Assistant may not work:
- Not signed in as an administrator
- Forgetting to turn off FileVault or iCloud
- The Mac is company-owned (Remote Management will stop you)
- Forgetting to deactivate Activation Lock
- Corrupt system files or a damaged hard disk on the Mac
If running Factory Reset Assistant isn’t an option, the only way to remove a virus is to carry out a factory reset using Recovery mode. This will manually erase the hard drive and reinstall macOS.
If you factory reset your Mac, don’t use an iCloud backup unless you are certain that the backup is free of malware.
To access the recovery menu, you first need to verify the type of MacBook you have.
Go to the Apple menu and select About This Mac. Look at the Chip category. If you see the letters M1, M2, M3, or M4, you have an Apple Silicon Mac. If it says Intel, then you have an older Intel-based Mac. This is important to note because the process slightly differs depending on the type of Mac you have.
If you have an Apple Silicon Mac:
- Completely shut down your Mac.
- Restart by holding the power button, and don’t release your finger until you see “Loading startup options.”
- Click options, then click the Continue button.
If you have an older Intel Mac:
- Restart the Mac.
- As soon as you begin the restart process, hold down the Command and R keys. Do not release your finger until the Apple logo appears.
In both cases, you will be taken into the Recovery menu. If you have locked down the firmware, you will need a password to remove that lock. If you don’t know the password, you cannot reset the system. The same goes for Filevault. If you’re unable to unlock it, you’re out of luck.
Once inside the Recovery menu, you can:
- Erase and reformat the hard drive using Disk Utility
- Reinstall macOS entirely
- Run commands on Terminal
- Access the Safari browser, which is useful if you need to make any Google searches
How can a virus return after a factory reset?
As we said previously, performing a factory reset to get rid of a virus will be effective in the majority of cases. The process will remove most malware and viruses.
If you’ve tried a factory reset and the virus or malware is still present, there are some possible reasons why your MacBook factory reset wasn’t effective.
Infected Time Machine backups
The most common reason is that your Time Machine backup contains the malware. When you restore your MacBook with the infected backup, you end up restoring the malware as well.
The malware is in your iCloud account
If your backup is stored in iCloud, the malware could also be there. Even a factory reset of your MacBook won’t work if iCloud simply syncs the malware back to your computer and any other connected devices.
Infected apps
If the malware entered your MacBook through a malicious app, reinstalling that app is going to reinstall the malware, too. It’s not just apps — this can happen with browser extensions or cracked software from pirate download sites.
You have a rootkit or Firmware malware infection
As we previously mentioned, malware can lurk in rootkits and firmware deep inside your MacBook. It’s highly difficult to remove these threats, as the process may involve replacing the firmware. The best solution, in this case, is to go to an Apple Store and have their experts remove it for you.
What to do if the virus comes back after a factory reset
Once you perform a factory reset on your MacBook, the viruses and malware that were present on your machine will be gone. But what if lightning strikes twice, and you end up with a new virus or malware incident?
Use CleanMyMac
Contrary to popular opinion, your Mac needs an antivirus solution. The most efficient and fastest tool to check for malware and viruses is to use CleanMyMac, powered by Moonlock Engine.
CleanMyMac will systematically scour your Macbook, collecting and removing malware hiding on your device. It’s a lightweight, fast, and powerful platform that comes with a free trial, so you can try it for yourself.
Once you have signed up for the free trial and installed CleanMyMac on the infected device, do the following:
- Click Protection in the left sidebar (look for the small raised hand icon). This opens the malware removal tool.
- Click Configure Scan to access and set your scan settings. Enable all options, then exit that screen.
- Hit the Scan button to begin the malware detection process. CleanMyMac will look for all infected files and quarantine them for your review.
- When malware threats have been found, CleanMyMac will show them to you in a complete list. Select them all and click Remove.
- Now select Cleanup, which is the feature above Protection. This will scan for and remove any junk files, including potentially infected files relating to the malware. Deleting these will ensure that absolutely no trace of the malware is left on your MacBook. Then remember to empty your trash bin.
Analyze where the viruses and malware are coming from
Getting a virus or malware once could be put down to bad luck. But if it happens a second time, maybe you have an unplugged gap in your defenses.
Here are a few actions to increase your cybersecurity on your Mac:
- Check to see if a macOS update is waiting.
- Update all of your installed apps. Ensure that you know all of the apps and that there are no suspicious programs present.
- Look over your Wi-Fi network for vulnerabilities. Is it password-protected, for example? Is the firmware up-to-date?
- Check your other devices. Are all other devices on your network virus-free?
- Is your Mac Firewall turned on?
- Do you have FileVault enabled?
Essential tips for safeguarding your MacBook against viruses
To avoid having to deal with MacBook viruses ever again, here are some tips to help you practice better security.
Never click on links from uncertain sources
If someone who you don’t know — or someone you don’t completely trust — sends you an email link or SMS link, don’t click it. It could lead to a malware-infected website or download a malicious file.
Put a strong password on your Wi-Fi network
Anyone looking to break into your Wi-Fi network is going to have an easy time of it if there’s no password blocking their way. Always put a very strong password on your network so only authorized visitors can get in.
And while we’re on the topic, don’t give your network a name that makes it obvious that it’s yours. If a hacker is specifically looking for you, a network with your name on it is like opening the door and waving them in.
Enable a VPN
It verges on impossible for a hacker to monitor your internet traffic if that traffic is being diverted through an encrypted VPN tunnel. That’s why using ClearVPN is a strong component of ensuring that viruses and malware are a thing of the past.
A VPN will block your real IP address and send everything through an encrypted server, bypassing anyone who may be attempting to eavesdrop on what you’re doing. It’s one of the best cybersecurity investments you’ll ever make.
Put a password on your Mac screen
A hacker doesn’t always need digital access to your Mac. They could simply sit in front of it and introduce malware directly. You only need to turn your back for 5 minutes.
Always make sure your Mac has a password to unlock the screen, and make sure you go to the lock screen before you leave the Mac unattended.
Only install apps from the Apple App Store
Another tried and true method for hackers is tricking you into installing compromised apps.
Anything that is in the Apple App Store for macOS or iOS has been vetted by Apple, examined for malware, and verified. So you can be assured that if you only download from there, you’ll be OK.
Keep your macOS and apps updated
There’s never any guarantee that your Mac will remain vulnerability-free. This is why Apple regularly pushes out updates. The same goes for apps. Developers bring out updates to squash bugs and seal up security holes.
Don’t be lackadaisical about this. Installing updates and patches is a very important part of Mac security. Check for new updates regularly or turn on the Automatic Updates option.
When you want to kill a virus or erase malware, the simplest and fastest solution is to wipe and factory reset your machine. Moonlock’s CleanMyMac will detect and remove viruses and malware itself, but for peace of mind, resetting your device is the next best thing to do.
This is an independent publication, and it has not been authorized, sponsored, or otherwise approved by Apple Inc. Mac, MacBook, macOS, iPhone, and iOS are trademarks of Apple Inc.
