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Microsoft Security Intelligence
Published May 28, 2014 | Updated Sep 15, 2017


Detected by Microsoft Defender Antivirus

Aliases: Trojan/Win32.Cryptolocker (AhnLab) W32/Ransom.XWLZ-0443 (Command) TR/Crypt.ZPACK.13648 (Avira) Trojan.GenericKDV.1279124 (BitDefender) Trojan.DownLoader10.17256 (Dr.Web) W32/Zbot.GFC!tr (Fortinet) Mal/Ransom-BZ (Sophos) TROJ_FRS.BMA000IP13 (Trend Micro)


Microsoft security software detects and removes this family of threats.

This ransomware family encrypts your files and shows you a webpage that asks you to pay a fee to unlock them.

They can be installed on your PC  by other malware, such as TrojanDownloader:Win32/Upatre and PWS:Win32/Zbot.gen!GO. It can also spread through infected removable drives, such as USB flash drives. 

You can read more about this type of threat 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

Use the following free Microsoft software to detect and remove this threat:

You should also run a full scan. A full scan might find other, hidden malware.

Advanced troubleshooting

You might be able to recover encrypted files by using the tool discussed in the MMPC blog post FireEye and Fox_IT tool can help recover Crilock-encrypted files.

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

Get more help

You can also visit our advanced troubleshooting page or search the Microsoft virus and malware community for more help.

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