Last Friday, a major ransomware attack hit the UK, United States, Russia and China, among others, with NHS England being ground to a halt. The ransomware, known as WannaCry, took advantage of people still using Windows XP, and people using Windows 7 without the latest security updates.

In NHS hospitals all over England, the ransomware attack led to staff being locked out of their computers, although it is believed that no confidential patient data was compromised. The way ransomware viruses work is by encrypting the data on a machine, and withholding the key to decrypt it until a sum of money is paid to the hacker.

The NHS is still largely on Windows XP, which Microsoft ceased to support over three years ago in April 2014. Some organisations, including the NHS, were paying Microsoft to get private support for the outdated operating system, due to the high costs associated with replacing every machine with the latest software. This deal came to an end in May 2015, however, and wasn’t renewed, meaning the NHS has been wide open to this kind of attack for two years.

A free piece of software has been developed to combat the WannaCry ransomware, known as WannaKey. To prevent this from happening to you, the best thing we can advise is to always keep your computer up to date, as Windows 7 users found out the hard way.