How to Remove a Trojan From Windows

What Causes This?

A Trojan usually gets onto a Windows PC when you install a fake app, open a malicious email attachment, download cracked software, or click a deceptive pop-up. Unlike obvious viruses, Trojans often pretend to be something useful so they can slip past you unnoticed. Once installed, they may add startup entries, drop extra files, change security settings, or download more malware in the background.

Common Symptoms

• Windows suddenly becomes slow, unstable, or crashes more often
• Unknown apps, pop-ups, or browser redirects start appearing
• Windows Security is disabled or won’t open properly
• High CPU, disk, or network usage from unfamiliar processes
• New startup programs or scheduled tasks show up without your permission

How to Fix It Manually

1. Disconnect your PC from the internet

   • Turn off Wi-Fi or unplug the Ethernet cable.
   • This helps stop the Trojan from communicating with remote servers or downloading more malware.

2. Boot into Safe Mode

   • Press Windows + I to open Settings.
   • Go to System > Recovery.
   • Under Advanced startup, click Restart now.
   • After restart, choose 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 a full Windows Security scan

   • Open Start, type Windows Security, and open it.
   • Click Virus & threat protection.
   • Select Scan options.
   • Choose Microsoft Defender Offline scan first, then click Scan now.
   • After the PC restarts and finishes, return to Scan options and run a Full scan.
   • If Defender finds threats, choose Remove or Quarantine.

4. Check for suspicious startup items and processes

   • Open Task Manager with Ctrl + Shift + Esc.
   • Click the Startup apps tab.
   • Disable anything unfamiliar or clearly suspicious by right-clicking it and selecting Disable.
   • Then check the Processes tab for apps using unusually high CPU, memory, or disk.
   • If you see a suspicious process, right-click it, choose Open file location, and note the folder path. Do not delete random system files unless you are sure they are malicious.

5. Remove suspicious apps and scheduled tasks

   • Press Windows + I, then go to Apps > Installed apps.
   • Sort by Install date and uninstall anything you don’t recognize that appeared around the time the problem started.
   • Next, press Start, type Task Scheduler, and open it.
   • In Task Scheduler Library, look for tasks with random names, strange triggers, or references to odd file paths. Disable suspicious entries.

6. Reset affected browsers

   • In Microsoft Edge, open the browser, click the three dots, then go to Settings > Reset settings > Restore settings to their default values.
   • Also check Extensions and remove anything you didn’t install.
   • If you use Chrome or Firefox, remove unknown extensions and reset the browser settings there too.

7. Repair system files

   • Right-click Start and choose Terminal (Admin) or Windows PowerShell (Admin).
   • Run these commands one at a time:
     1. sfc /scannow
     2. DISM /Online /Cleanup-Image /RestoreHealth
   • These tools can repair Windows files damaged by malware.

8. Change important passwords after cleanup

   • Once scans are clean and the PC is stable, change passwords for email, banking, and other important accounts from a known-safe device if possible.
   • If the Trojan included spyware or a keylogger, your credentials may have been exposed.

Fix It Automatically with Kudu

Manual cleanup often removes the main infection but leaves behind broken startup entries, junk files, invalid tasks, and system instability. Kudu can help detect those malicious leftovers, clean them up safely, and improve Windows performance after a Trojan infection. It’s a faster way to get your PC back to normal without hunting through every setting yourself.

Download Kudu Free →