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Microsoft Security Intelligence
Published Nov 11, 2012 | Updated Sep 15, 2017

Trojan:Win32/Loktrom.B

Detected by Microsoft Defender Antivirus

Aliases: Spyware/Win32.Zbot (AhnLab) TR/Ransom.EZ.577 (Avira) Trojan.Ransomlock!g33 (Symantec) Trojan.Winlock.6049 (Dr.Web) Trojan-Dropper.Win32.Dapato (Ikarus) Trojan-Ransom.Win32.Gimemo.attq (Kaspersky)

Summary

Windows Defender Antivirus detects and removes this threat.

If this threat asks you to pay a fee or fine, do not pay it. The message is a fraud.

This family of ransomware locks your PC and displays a full-screen message (commonly called a "lock screen").

It pretends to be from a national police force and tries to scare you into paying a fine to unlock your PC.

See the Technical information tab for examples of the lock screen.

Typically, this threat gets onto your PC from a drive-by download attack. It might also have installed itself on your PC if you visit a compromised webpage.

You can read more on our ransomware page.

There is no one-size-fits-all response if you have been victimized by ransomware. There is no guarantee that paying the ransom will give you access to your files.

If you've already paid, see our ransomware page for help on what to do now.

Run antivirus or antimalware software

The following free Microsoft software detects and removes this threat:

Even if we've already detected and removed this particular threat, running a full scan might find other malware that is hiding on your PC.

Advanced troubleshooting

To restore your PC, you might need to download and run Windows Defender Offline. See our advanced troubleshooting page for more help.

You can also ask for help from other PC users at the Microsoft virus and malware community.

If you’re using Windows XP, see our Windows XP end of support page.

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