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How to Remove a Virus From Your Computer

8 min read  ·  Works on Windows 10, Windows 11, and macOS

Suspecting a virus on your computer is scary — but most malware infections are removable without wiping your machine or paying anyone. This guide explains how to confirm you actually have malware, remove it safely, and make sure it doesn't come back. Stay calm and work through these steps.

Signs Your Computer Might Have a Virus

If you're seeing two or more of these, proceed with the removal steps below.

Don't call any number that pops up on your screen. "Your computer has a virus — call Microsoft at 1-800-XXX-XXXX" is itself a scam. Microsoft, Apple, and antivirus companies never display phone numbers in pop-ups asking you to call them.

Step-by-Step Removal

1

Disconnect from the internet

Turn off your WiFi or unplug your ethernet cable. This stops the malware from sending data to attackers or downloading additional malicious files while you work on removing it.

2

Run Windows Defender (Windows)

Click the Start menu and search for Windows Security. Click Virus & threat protection, then Scan options, and select Full scan. Click Scan now. This takes 30–60 minutes but checks every file on your computer. It's built into Windows and completely free — and it's genuinely effective.

3

Run Malwarebytes as a second opinion

Download Malwarebytes Free from malwarebytes.com (reconnect to the internet just to download, then disconnect again). Install it and run a Threat Scan. Malwarebytes catches many types of malware that traditional antivirus misses. The free version is sufficient for a one-time cleanup.

4

Check your browser for unwanted extensions

Many infections install browser extensions that show ads or redirect searches. In Chrome, go to Settings › Extensions. In Firefox, go to Add-ons and themes. Remove anything you don't recognise or didn't intentionally install. Also check your homepage and default search engine settings.

5

Check startup programs for anything suspicious

On Windows, right-click the taskbar and open Task Manager › Startup tab. Look for anything unfamiliar with "Enabled" status. Right-click suspicious entries and select Disable. On Mac, go to System Settings › General › Login Items and remove anything unrecognised.

6

Change your important passwords

After cleaning the infection, change passwords for your email, banking, and any site where you store payment information. Do this from a different device if possible, or wait until you've confirmed the malware is gone. Some malware logs keystrokes — better to be safe.

Mac users: Macs can get malware too, though it's less common. Malwarebytes has a free Mac version. Also check System Settings › Privacy & Security › Extensions for anything suspicious, and review Login Items for unrecognised entries.

If Nothing Works: Factory Reset

If scans find malware but can't remove it, or the computer still behaves strangely after cleaning, a factory reset is the nuclear option — it removes everything and starts fresh. Back up your important files first (to an external drive or cloud storage). On Windows, go to Settings › System › Recovery › Reset this PC. It takes about an hour but guarantees a clean machine.

Not sure what you're dealing with?

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