If your phone has fallen prey to a virus, you might consider performing a factory reset to remove it. While a factory reset can be an effective solution, it's never an easy choice. You lose all your data as you revert your phone to its original state.

Theoretically, a factory reset should erase all viruses from your phone, but it’s not always the case. Not all viruses go away during a factory reset. It’s better to understand the odds of success before initiating the process. So what does a factory reset really do? How can viruses survive such a Scorched Earth approach?

What Does a Factory Reset Do?

A factory reset allows you to revert your smartphone to its original state—the state in which it first came from the company. It erases all the information, including photos, movies, system files, and apps on your device. Factory resets only leave the most basic set of software that came pre-installed from the manufacturer.

Since factory resets basically clear everything stored on a phone, viruses and other malware can also be removed with it. But does it remove all viruses from the phone?

Does Factory Reset Remove Viruses from Your Phone?

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The short answer is “yes”! By returning the phone settings to factory model, the reset option automatically deletes viruses and any infected file or program on your device. It’s an extreme option and works pretty much every time—except in some very rare cases.

Viruses are constantly evolving and cybercriminals are exploring new ways to infiltrate the phones of unsuspecting individuals and evade detection. One such virus is xHelper: this emerged in March 2019 and targeted Android devices. It infiltrated phones by hiding in the code of unverified Android apps that were available outside the Play Store.

Once installed, xHelper would serve spam notifications and annoying pop-ups on users’ phones. But the worst part was its distinctive ability to evade factory resets. XHelper would disappear momentarily after resetting, but it would reactivate itself after a few hours.

How Do Viruses Survive Factory Reset?

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A factory reset will generally remove viruses, but a few can still survive it. Here are some ways this can happen:

  1. It’s rootkit malware: A rootkit is malicious software that provides privileged access to the operating system of a device. Once installed, a rootkit will allow cybercriminals to gain administrator-level control over a device without being detected.
  2. The backup is infected: Since factory reset deletes all data on a phone, most users choose to back up their device to avoid data loss. If the backup contains an infected file or program, and you restore it without scanning, you will restore the same virus to your device.
  3. The peripheral devices are infected: Some malware can take shelter in the peripheral devices, like external keyboards or Wi-Fi adapters, connected to your phone. Many such devices have onboard storage, so viruses can use it to keep a copy of itself. So even if you reset your phone, the virus can still reactivate itself from the peripherals.

Things to Consider Before Resetting Your Phone

A factory reset is a complete software restore of your phone. It wipes all data and brings your device back to its original state. But before you initiate this process, there are a few things you need to keep in mind.

  • It’s an irreversible process: Once you hit the erase content and reset button, there’s no coming back. You can’t pause the process nor can you interrupt it. Otherwise, you will end up with a non-functional phone with no essential software to run it.
  • There are multiple system restore options: There are usually two types of resets you can perform on a phone; a hard reset, also called factory reset, and soft reset. A hard reset erases all data and reverts the phone to its default settings. A soft reset doesn’t remove any data and works like an extended reboot. It can resolve minor issues like abnormal battery behavior or problems with built-in apps. Some phones also offer options to reset Wi-Fi, Bluetooth, and app preferences, none of which will wipe your phone storage.

Now that you understand the different reset options and what each entail, you need to know how to perform a factory reset.

How to Factory Reset an Android Phone

Doing a hard reset is quite similar on most Android devices. Here are the steps you need to take to start the process.

  1. Open the Settings app on your phone.
  2. Tap System > Reset options. The wording may be different depending on your phone’s brand.
  3. Among the reset options, select Erase all data (factory reset).
  4. A dialog box appears showing you all the content that will be affected by the full reset. Tap Erase all Data at the bottom of the screen.
  5. Enter your PIN or password and press Continue. This appears only if you’ve set up an authentication method on your phone.
  6. Tap Erase all Data to initiate the process.

If the above method doesn’t work for you, there are other ways you can factory reset your android phone.

How to Factory Reset an iPhone

Just like Android devices, there are a few ways to reset your iPhone. To perform a hard reset from the device itself, follow these steps:

  1. Go to Settings > General > Reset.
  2. You will see different reset options. Tap Erase all Content and Settings.
  3. A new screen asks you to update your iCloud backup. If you haven’t already backed up your data, select Back Up Then Erase. Otherwise, tap Erase Now.
  4. Enter your passcode and tap Erase in the dialog box that appears.
  5. Another dialog box shows up to confirm that you’re about to wipe your device. Tap Erase and the reset process will start.

A Factory Reset Should be Your Last Option

A factory reset is never an ideal option to get rid of a virus. You risk losing all your data and there’s no guarantee that it will work. While the type of malware that can survive a hard reset is rare, it’s best that you take precautionary measures to protect your phone.

Using a good antivirus software can be handy, but we also recommend performing regular security checks to ensure that your phone is fully protected.