How to Remove a Virus From Windows

What Causes This?

Viruses and other malware usually get onto Windows through unsafe downloads, fake software installers, malicious email attachments, browser pop-ups, or infected USB drives. Some threats also arrive bundled with cracked apps or “free” tools that install hidden background processes. Once active, they can change startup settings, create scheduled tasks, disable security tools, and leave behind junk files even after the main infection is removed.

Common Symptoms

• Your PC suddenly becomes slow, noisy, or unusually hot when idle
• Pop-ups, redirects, or unwanted apps appear in your browser or desktop
• Windows Security is turned off or won’t open properly
• Unknown programs start automatically when you sign in
• Files go missing, settings change on their own, or storage fills up unexpectedly

How to Fix It Manually

1. Disconnect from the internet

   • Turn off Wi-Fi or unplug your Ethernet cable.
   • This can stop the virus from downloading more malware or sending data out.

2. Restart into Safe Mode

   • Press Windows + I to open Settings.
   • Go to System > Recovery.
   • Under Advanced startup, click Restart now.
   • After restart, select Troubleshoot > Advanced options > Startup Settings > Restart.
   • Press 4 for Safe Mode or 5 for Safe Mode with Networking if you need internet access for updates.

3. Run Microsoft Defender Offline

   • Open Start, type Windows Security, and open it.
   • Click Virus & threat protection.
   • Under Scan options, choose Microsoft Defender Offline scan.
   • Click Scan now and let your PC restart and scan.
   • This helps remove malware that hides while Windows is running normally.

4. Run a full antivirus scan after reboot

   • Open Windows Security > Virus & threat protection again.
   • Click Scan options and select Full scan.
   • Remove or quarantine anything it finds.
   • If Defender is disabled or keeps failing, that can be a sign the infection is still active.

5. Check for suspicious startup apps and processes

   • Open Task Manager with Ctrl + Shift + Esc.
   • Click Startup apps and disable anything unfamiliar or clearly unwanted.
   • Then check the Processes tab for apps using high CPU, memory, or disk for no clear reason.
   • If you find something suspicious, right-click it and choose Open file location to inspect it before ending the task.

6. Uninstall suspicious programs

   • Press Windows + I and go to Apps > Installed apps.
   • Sort by Install date and look for recently installed programs you don’t recognize.
   • Click the ... menu next to a suspicious app and choose Uninstall.
   • Avoid removing drivers, Microsoft components, or software you know is legitimate.

7. Clean temporary files and update Windows

   • Press Windows + R, type %temp%, and delete the files you can.
   • Then go to Settings > System > Storage > Temporary files and remove unnecessary items.
   • Finally, go to Settings > Windows Update and install all available updates.
   • Security updates can close the hole the malware used to get in.

8. Change important passwords after the system is clean

   • Once scans come back clean, change passwords for email, banking, and other important accounts.
   • Do this from the cleaned PC or another trusted device.
   • If the virus included spyware or a password stealer, this step matters.

Fix It Automatically with Kudu

Kudu can help remove malicious leftovers that antivirus tools often miss, including broken startup entries, temporary files, invalid scheduled tasks, and other system clutter left behind after an infection. It gives you a faster way to clean up Windows and restore normal performance without digging through every system folder manually.

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