Microsoft Defender Antivirus detects and removes this threat.

This threat stops you from loading Windows and displays a full-screen message, commonly called a "lock screen". If this threat asks you to pay a fee or fine, do not pay it. The message is a fraud.

It tries to scare you into paying a fine or texting a premium-charge phone number to unlock your PC.

You can read more on our ransomware page.

The trend towards increasingly sophisticated malware behavior, highlighted by the use of exploits and other attack vectors, makes older platforms so much more susceptible to ransomware attacks. From June to November 2017, Windows 7 devices were 3.4 times more likely to encounter ransomware compared to Windows 10 devices.

Read our latest report: A worthy upgrade: Next-gen security on Windows 10 proves resilient against ransomware outbreaks in 2017.