Last updated: May 25, 2026 · 5 min read

How to Scan Your Computer for Viruses

Why You Should Scan Your Computer Regularly

Scanning your computer for viruses is like taking your car in for regular maintenance. It helps catch problems before they become serious. Viruses and malware can steal your personal information, slow down your computer, or even lock your files and demand money.

The FBI’s Internet Crime Complaint Center reports that adults over 60 lose more to online fraud than any other age group — over $3.4 billion in 2023. Many of these scams start with infected computers. Regular scans help protect you.

Don’t worry if you’ve never scanned before. Your computer has built-in tools that make this simple. You don’t need to buy expensive software or be a computer expert.

How to Run a Quick Virus Scan on Windows

A quick scan checks the most common places where viruses hide. This is the scan you should run weekly. Here’s how to do it step by step:

1. Open Windows Security: Click the Start button in the bottom left corner of your screen. Type “Windows Security” and press Enter. A blue shield icon should appear.
2. Go to Virus & Threat Protection: Click on “Virus & threat protection” in the menu. This opens the main security page where you can scan your computer.
3. Start the Quick Scan: Click the blue “Quick scan” button. Your computer will start checking for viruses right away. Don’t worry if it takes several minutes.
4. Wait for Results: The scan usually takes 5 to 15 minutes. You can keep working while it runs. A message will tell you when it’s done.
5. Review What Was Found: If Windows Security finds anything suspicious, it will show you a list. Most of the time, it removes threats automatically. You just need to click “Start actions” if prompted.

You’ve got this. The process is straightforward and Windows guides you through each step. If the scan finds nothing, you’ll see a green checkmark that says “No current threats.”

How to Run a Full Virus Scan

A full scan checks every file on your computer. This takes longer but is more thorough. Run a full scan once a month, or if your computer is acting strange.

1. Open Windows Security: Click Start, type “Windows Security,” and press Enter, just like before.
2. Go to Scan Options: Click “Virus & threat protection,” then click “Scan options” just below the Quick scan button.
3. Choose Full Scan: Click the circle next to “Full scan” to select it. Then click the “Scan now” button at the bottom.
4. Let It Run: A full scan can take one to three hours. It’s best to start this when you won’t need your computer for a while. You can use your computer during the scan, but it might run slower than usual.
5. Check the Results: When finished, Windows Security will tell you what it found. Follow any instructions to remove threats.

Most people fix this in under 5 minutes of setup time. The computer does all the hard work while you go about your day.

Warning Signs That You Might Have a Virus

Sometimes your computer will tell you something is wrong before you even run a scan. Here are the most common warning signs:

• Your computer runs much slower than usual, especially when starting up
• Pop-up ads appear even when you’re not using a web browser
• Programs open or close by themselves
• Your homepage changed without you changing it
• New toolbars or programs appear that you didn’t install
• Your friends receive strange emails from your account
• You can’t open Windows Security or it won’t run

If you notice any of these signs, run a full scan right away. If Windows Security won’t open or keeps closing, that’s a red flag. Some viruses try to disable your security software.

What to Do If Windows Security Finds a Virus

Finding a virus can feel scary, but Windows Security makes removal simple. Here’s what happens:

When the scan finishes, Windows Security will show you a list of threats. Each one is labeled as low, medium, high, or severe. The software recommends an action for each threat — usually “Remove” or “Quarantine.”

Quarantine means the file is isolated so it can’t harm your computer. It’s like putting it in jail. Remove means Windows deletes it completely. In most cases, you should follow the recommended action.

Click “Start actions” to let Windows Security clean up the threats. This takes just a minute or two. When it’s done, you’ll see a confirmation message.

After removing viruses, restart your computer. This makes sure all the changes take effect. Your computer should run better right away.

Don’t worry if you’re unsure about a threat. If you need help understanding what was found, our virus & malware removal service can walk you through it.

How to Keep Your Computer Protected

Scanning is important, but prevention is even better. Follow these simple habits to keep viruses away:

First, keep Windows Security turned on. It should run automatically in the background. To check, open Windows Security and look for green checkmarks. If you see yellow or red warnings, click them and follow the instructions.

Second, install Windows updates when your computer asks you to. These updates fix security holes that viruses use to sneak in. Your computer will remind you when updates are ready. Don’t ignore these reminders.

Third, be careful what you click. Don’t open email attachments from people you don’t know. Don’t click links in suspicious emails, even if they look like they’re from your bank. When in doubt, call the company directly using a phone number you look up yourself.

Fourth, only download programs from websites you trust. If a pop-up says you need to download something to “fix” your computer, close it. That’s often how viruses spread.

When Should You Ask for Help Instead of Fixing It Yourself?

Some virus problems are easy to fix on your own. Others need expert help. Here’s when to call in the professionals:

• Windows Security won’t open or keeps crashing when you try to scan
• You see messages demanding money to unlock your files (this is called ransomware)
• Your computer is so slow you can barely use it, even after scanning
• You removed viruses but still see pop-ups or strange behavior
• You’re worried you might have given personal information to a scammer

These situations often mean the virus is more serious or has changed important settings. Professional help can save you hours of frustration. Our virus & malware removal service can connect to your computer remotely and fix these problems while you watch. No home visit needed.

You’re Taking the Right Steps

Learning to scan your computer for viruses is an important skill. You’re protecting yourself, your information, and your peace of mind. Even if technology feels confusing sometimes, you’re capable of handling this.

Start with a quick scan today. Set a reminder to run one every week. Once a month, run a full scan. These simple habits will keep your computer healthy and safe.

Remember, everyone deals with computer problems sometimes. You’re not alone, and help is always available when you need it.