Can New Antivirus Software Remove Existing Viruses?

Your computer has a virus, but your antivirus program is outdated — or worse — you don’t have protection. Will installing new antivirus software remove your existing virus? This article will explain how how antivirus software does and doesn’t work.
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Have you recently discovered a computer virus has taken hold of your device? What if you have antivirus software now but think your computer still got attacked by malware? Many people wonder if a new antivirus program will remove an existing virus, and the answer is — that depends.

Not all antivirus programs offer the same level of malware protection. Some programs can remove an existing virus as soon as you install them, but not all will. New malicious software can be sophisticated, so if you have a computer virus, you need to know how to get it off your machine quickly. We’ll explore antivirus software and elaborate on the limitations and security features to consider below.

In this article
Can antivirus software remove existing viruses?
What antivirus software is best for removing viruses?
How to check for computer viruses
How to uninstall antivirus software
Bottom line

Can antivirus software remove existing viruses?

Yes, antivirus software can remove some existing viruses. Antivirus software is typically designed to prevent your device from getting a virus, so you need to know what features come with the security software. If you want to know how to remove existing viruses, running an antivirus scan is your first step.

An antivirus program will scan through your device’s files and folders. Most programs allow full and quick scanning options. A full system scan is a thorough check of the whole system, while a quick scan just checks the areas most susceptible to malware. Depending on the security software you buy, antivirus programs can protect you from malware threats like ransomware, spyware, trojans, worms, phishing, and more.

Antivirus programs scan your device for suspicious activities and can remove infected files once found. But virus removal may be trickier if you have an existing virus. Sophisticated malware can bypass some software and remain hidden on your computer. This is where anti-malware software comes in handy, as it works to prevent and remove malware, including the more modern varieties like keyloggers and phishing.

What is the difference between antivirus software and malware removal?

First, it’s necessary to understand that all computer viruses are malware, but not all malware are viruses.

Antivirus software is built to protect your device against established threats, like traditional viruses. Some examples of these would be trojans and worms. These are predictable threats. However, older security software may not detect newer, more complex threats.

Malware removal is helpful because newer threats like zero-day infections and replicating files, e.g., polymorphic viruses, are good at hiding from antivirus software.

The good news is that you don’t have to choose between reliable antivirus software and the best anti-malware software. Many antivirus programs have both, so investing in comprehensive security software is important.

Types of malware

Malware type How malware works Example of malware attacks
Adware Sends unwanted pop-ups for ads Fireball
Bots/botnets Launches a flood of various attacks Echobot
Fileless malware Changes native OS files Astaroth
Keyloggers Monitors users’ keystrokes Olympic Vision
Logic bombs Activates malware from a specific trigger Siemens spreadsheet issue 2016
Ransomware Disables user access until a ransom is paid RobbinHood
Rootkits Allows remote access to the user’s device Zacinlo
Spyware Collects data from users without consent or knowledge DarkHotel
Trojans Disguises invasions as real programs Emotet
Viruses Executes code when an app runs Stuxnet
Wiper malware Erases data that cannot be recovered WhisperGate
Worms Spreads through a network, replicating itself continuously SQL Slammer

What antivirus software is best for removing viruses?

Many antivirus programs may be effective, but your level of protection depends on your needs. For instance, are you more concerned with reliability and performance? Conversely, you may be on a budget and only need the bare minimum of virus protection. Are there necessary antivirus software features that you require more than others?

Some users prioritize ease of use and want a simple interface that won’t take much time to learn. Others may enjoy a more intricate system that allows for customization. If you’re wondering how to choose the best security software for removing viruses, here are some specs you may want to remember when browsing antivirus programs:

  • Real-time protection that checks for threats while you work
  • Manual and scheduled system scan capabilities
  • Phishing and ransomware protection to secure your data
  • Coverage for multiple devices, like smartphones, computers, and tablets

The best antivirus software for Windows

If your computer has a Windows operating system, you need antivirus protection. Because Windows is the most popular operating system, hackers are likelier to target Windows users. Historically, Windows users must manually download applications from websites instead of a secured app store. As a result, users may unwittingly download malware directly from their browsers, making the system more vulnerable to malware attacks.

The best antivirus for Windows will include real-time protection and other features to keep your computer secure. We have a few recommendations for you below:

  • McAfee: McAfee provides all-in-one protection with features like parental controls, a firewall, and a file shredder.

    Get McAfee | Read McAfee Review

  • Norton: Norton is a popular software for Windows, providing options like a secure VPN, a password manager, and parental controls.

    Get Norton | Read Norton Review

The best antivirus software for Mac

As a Mac user, you’ll want to protect your device from dangerous malware threats. For enhanced macOS cybersecurity, you’ll want to get software designed to meet your needs. Below are suggestions for the best antivirus software for Mac:

  • Avast: Avast is recommended for users who want multiple device security but aren’t concerned with parental controls or family protection.

    Get Avast | Read Avast Review

  • MacKeeper: MacKeeper is built specifically for macOS, includes features like ID Theft Guard, and provides excellent customer support.

    Read MacKeeper Review

How to check for computer viruses

If you think you have a virus, run a manual scan on your device. We recommend running a full system scan because it’s more thorough and will check drives and folders that the quick scan may not.

When you want to conduct security maintenance but don’t necessarily suspect a threat, you can run a quick virus scan as a precaution.

In more extreme cases, like your operating system not launching, you may need to reboot your computer and enter safe mode. That will launch your necessary basic startup programs.

How to run antivirus software on Windows

Running an antivirus scan on Windows is straightforward. There may be changes depending on the antivirus software you use, but these are the basic steps:

  1. Open your antivirus software.
  2. Go to Scans and click on Full Scan or Quick Scan.
  3. Click Go or OK.

How to run antivirus software on macOS

Using an antivirus to scan your Mac is similar to using one for Windows. In this example, we’ll show you how to use MacKeeper to detect and remove malware threats:

  1. Open your antivirus program.
  2. Click Start Scan.
  3. If you want to scan a specific area, you can choose Custom Scan.

How to uninstall antivirus software

If you already have antivirus software but want to download a different one, uninstall or disable the old program first. You shouldn’t use two antivirus programs simultaneously because they can slow down your device.

Antivirus software can take up a lot of RAM on your computer, and you don’t need to double that space. In some instances, the entire computer may crash from both programs running at once. In other cases, one antivirus program might interfere with the other, adversely affecting your device's performance.

Here’s how to disable antivirus software to avoid these issues.

Removing antivirus software on Windows or Windows 10

  1. On the taskbar, choose the antivirus program to uninstall.
  2. Right-click on the program and select Shut Down Protection.
  3. Click Yes if prompted.

Removing antivirus software on macOS

  1. Press the Command button and spacebar together.
  2. Type the antivirus program’s name in the search window.
  3. Open the program’s interface.
  4. Select Stop, Turn off, or Disable.
  5. Click OK or Yes to confirm if prompted.

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Can viruses get past antivirus software?

Depending on the malware’s complexity, some new viruses can get past antivirus software. Some threats are new, like polymorphic viruses that software vendors aren’t aware of, so it’s easy for them to avoid virus detection.


How do I know if my antivirus software is working?

One way to know if your antivirus software is working is to run frequent scans. But if you’re unsure of whether the program is installed correctly, locate the application via Control Panel > System and Security. You can launch the program directly and confirm its status.


Should I remove the old antivirus software before installing a new antivirus program?

Yes, you should always uninstall or disable your current antivirus software before installing a new antivirus program. Concurrently running antivirus programs will compete, which can cause your battery to drain or your computer to slow down or crash. You may also see a drastic drop in device performance if both programs offer real-time protection.

Bottom line

New antivirus software can remove existing viruses, but it depends on what kind of malware infection you have and what your specific software protects against. Not all antivirus programs offer the same cybersecurity features.

Only use one antivirus program at a time, as having two running programs can cause system crashes. More is not always better, especially in this case. With so many new modern threats, you want to use the best antivirus software for your device.

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Author Details
Patti Croft is a seasoned writer specializing in technology, with three years of experience. With a B.S. in Computer Science and a background as a technical analyst and security specialist, she covers a range of topics like data security and parental control software.