Remove Computer Viruses: A Step-by-Step Guide

TL;DR

This guide shows you how to remove computer viruses and protect your computer in the future. It covers scanning, removal tools, safe browsing habits, and keeping your software up to date.

1. Identify the Virus

Knowing what kind of virus you’re dealing with can help. Common signs include:

• Slow computer performance
• Unexpected pop-up windows
• Programs starting on their own
• Unusual error messages
• Changes to your homepage or search engine

If you can, note the name of any virus warnings or files involved.

2. Disconnect from the Internet

This stops the virus from spreading and sending information. Unplug your network cable or disconnect from Wi-Fi.

3. Run a Full System Scan with Your Antivirus Software

Your existing antivirus is your first line of defence. Make sure it’s up to date before scanning:

1. Update Definitions: Most antivirus programs have an ‘Update’ button or automatically update in the background. Check this first!
2. Full Scan: Select a ‘Full System Scan’. This will take a long time (potentially hours), but it checks every file on your computer.
3. Quarantine/Remove: Follow the antivirus software’s instructions to quarantine or remove any detected threats.

Examples of popular antivirus programs include Norton, McAfee, Bitdefender and Windows Defender.

4. Use a Second Opinion Scanner

Sometimes, one antivirus program misses things. A second opinion scanner can find additional threats:

• Malwarebytes: https://www.malwarebytes.com (Free version is sufficient for scanning and removal)
• HitmanPro: https://www.hitmanpro.com (Trial available)

Download, install, update, and run a scan with one of these tools.

5. Boot into Safe Mode

Safe Mode starts Windows with only essential drivers and services. This can help remove viruses that are difficult to deal with normally:

1. Restart your computer.
2. Press F8 repeatedly as the computer restarts (or Shift+F8 on some systems). You might need to try this a few times.
3. Select ‘Safe Mode’ or ‘Safe Mode with Networking’.
4. Run another full system scan in Safe Mode using your antivirus and/or second opinion scanner.

If you can’t get into safe mode, consult your computer manufacturer’s website for specific instructions.

6. Check Your Browser Extensions

Malicious browser extensions can cause problems. Remove any suspicious or unwanted extensions:

• Chrome: Type chrome://extensions in the address bar and press Enter.
• Firefox: Type about:addons in the address bar and press Enter.
• Edge: Type edge://extensions in the address bar and press Enter.

Disable or remove any extensions you don’t recognise or trust.

7. Reset Your Web Browsers

Resetting your browser restores it to its default settings, removing potentially harmful changes:

• Chrome: Settings > Advanced > Reset and clean up > Restore settings to their original defaults
• Firefox: Help > Troubleshooting Information > Refresh Firefox
• Edge: Settings > Reset settings > Restore settings to their default values

Be aware this will remove your saved passwords, cookies and browsing history.

8. Keep Your Software Updated

Software updates often include security patches that fix vulnerabilities viruses can exploit:

• Windows Updates: Settings > Update & Security > Windows Update
• Other Programs: Check for updates within each program’s settings (e.g., Adobe Reader, Java).

Enable automatic updates whenever possible.

9. Practice Safe Browsing Habits

• Avoid suspicious websites: Don’t click on links in emails or messages from unknown senders.
• Be careful with downloads: Only download software from trusted sources.
• Use a strong password manager: This helps you create and store unique, secure passwords.

10. Consider cyber security Software

For ongoing protection, consider installing comprehensive cyber security software that includes features like real-time scanning, firewall protection, and web filtering.