Signs Your PC Has a Virus—and How to Fix It

Viruses and other forms of malware can wreak havoc on your computer—stealing personal information, slowing down performance, or even making your system unusable. While not every computer issue is caused by a virus, knowing the warning signs can help you take action before serious damage occurs.

In this guide, we’ll cover the most common signs your PC might have a virus and provide practical steps to remove infections and protect your system.

Common Signs of a Virus Infection

Not all viruses behave the same way, but here are some of the most frequent symptoms:

1. Slow Performance

If your PC suddenly becomes sluggish—taking longer to boot, open programs, or browse the web—it could be a virus using system resources in the background.

2. Frequent Crashes or Freezes

Malware can interfere with normal system processes, causing unexpected shutdowns, blue screens, or apps that stop responding.

3. Excessive Pop-Ups and Ads

Unwanted pop-up ads, even when you’re not browsing the web, are a strong indication of adware or spyware infections.

4. Programs Launching on Their Own

If applications open or close without your input, malicious software may be controlling parts of your system.

5. Unknown Processes in Task Manager

Viruses often run hidden processes. If you notice suspicious names in Task Manager consuming high CPU or memory, it’s a red flag.

6. Disabled Security Software

If your antivirus or firewall turns off without your permission, a virus may be trying to weaken your defenses.

7. Unusual Network Activity

Constant background internet activity, even when you’re not using your PC, could mean malware is sending data to hackers.

8. Corrupted or Missing Files

Some viruses delete, modify, or lock files, making them inaccessible.

9. Browser Hijacking

If your homepage or search engine changes by itself, or you’re redirected to strange websites, you likely have a browser hijacker.

10. Overheating and Loud Fans

When malware consumes too much CPU power, your computer may overheat, causing fans to run constantly.

How to Fix a Virus Infection

If you suspect your PC has a virus, don’t panic. Here’s how to clean it step by step:

Step 1: Disconnect from the Internet

This stops the virus from spreading further or sending your data to hackers.

Step 2: Boot into Safe Mode

Press Windows + R, type msconfig, and hit Enter.
Under the Boot tab, check Safe boot → Network.
Restart your computer.

Safe Mode loads only essential drivers, making it easier to detect and remove malware.

Step 3: Run Windows Security (Defender)

Open Start → Settings → Update & Security → Windows Security.
Select Virus & Threat Protection.
Run a Full Scan to detect and remove malware.

Step 4: Use Free Malware Removal Tools

If the virus persists, use trusted free tools like:

Malwarebytes Free – excellent at detecting hidden malware.
AdwCleaner – removes browser hijackers and adware.
ESET Online Scanner – cloud-based detection.

Step 5: Uninstall Suspicious Programs

Press Windows + R, type appwiz.cpl, and press Enter.
Sort by installation date and remove anything unfamiliar or unwanted.

Step 6: Reset Your Browser

Viruses often hijack web browsers.

In Chrome/Edge/Firefox → go to Settings → Reset Settings.
Remove unknown extensions.

Step 7: Delete Temporary Files

Viruses sometimes hide in temp folders.

Press Windows + R, type %temp%, and delete all files.

Step 8: Restore System Settings (Optional)

If your PC still misbehaves, roll back to an earlier restore point:

Press Windows + R, type rstrui, and press Enter.
Choose a restore point before the infection.

Step 9: Update Windows and Software

After cleanup, update your system. Viruses often exploit outdated software.

How to Prevent Future Infections

Keep Windows and drivers updated.
Use Windows Defender + occasional scans with Malwarebytes Free.
Avoid downloading cracked or pirated software.
Be cautious with email attachments and suspicious links.
Use strong, unique passwords for accounts.
Backup important files to an external drive or cloud storage.

Conclusion

A virus can cause serious problems, from slow performance to stolen data. By recognizing the signs early—like random pop-ups, crashes, or unusual processes—you can take action before the infection worsens.

Using Windows Defender, free malware removal tools, and safe browsing practices, you can fix most infections without spending money. Most importantly, adopting good security habits will help keep your PC virus-free and running smoothly in the future.

Also Read :