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cloudff7's avatar
cloudff7
Copper Contributor
Oct 20, 2025

Question Trojan:Win32/Wacatac.C!ml

I perform complete scan in my PC using Microsoft Defender and detected AppData\Roaming\Secure\QtWebKit4.dll (Trojan:Win32/Wacatac.C!ml) this malware behavior modify, delete and corrupt my personal fi...
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AladinH's avatar
AladinH
Brass Contributor
Oct 20, 2025

Hi cloudff7​,

That alert means Defender caught a trojan that can change system settings or download other malware, but it usually doesn’t affect your personal files.

If Defender quarantined or removed it, you’re probably fine - just update Defender, run another full scan, and delete the AppData\Roaming\Secure folder if it’s still there.

You can also run Microsoft Safety Scanner to double-check.

Lucaraheller's avatar
Lucaraheller
Brass Contributor
Oct 21, 2025

 

That alert indicates that Microsoft Defender detected a trojan capable of modifying system settings or downloading additional malware. The good news is that these threats typically don’t target your personal files directly.

If Defender has already quarantined or removed the file, your system is most likely safe.
To make sure everything is clean, follow these steps:

  1. Update Microsoft Defender to the latest definitions.
  2. Run a full system scan to confirm there are no remaining threats.
  3. If you still see the folder AppData\Roaming\Secure, delete it manually.
  4. (Optional) Use the Microsoft Safety Scanner as an additional check for peace of mind.

After these steps, you should be fully protected and ready to continue using your device normally.

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