Preventing cyber attacks must be approached “pro-actively” by the public and it is “critical” businesses do more to protect themselves, security experts have warned.

Ransomware and other forms of malware continue to affect personal and business computers, with NHS England declaring a major incident in the wake of a cyber attack.

What is ransomware?

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Ransomware is a form of malicious software or malware that secretly installs itself on a user’s computer before blocking access to files and threatening to delete them unless a ransom is paid within a time limit.

How does it install itself?

(Dominic Lipinski/PA)


The most common form of attack is for hackers to hide the virus within harmless-looking emails that contain links, which users are then tricked into clicking on.

Opening the links will then covertly install the malware onto the computer without the user’s knowledge, giving it access to the computer’s files. It is at this point that the virus encrypts and locks the files and demands the ransom.

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However, it can also be hidden within applications available to download from unofficial or unauthorised websites.

Can ransomware be removed?

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With advanced anti-virus software, it is possible to remove the virus from a computer. It can also be done manually by putting a computer into “safe mode” and manually removing the infected files.

However, prevention remains the best form of defence.

How can ransomware infection be prevented?

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Security experts say users should ensure their computer software is always up to date. Often important security updates are contained within these downloads and can prevent known viruses from infecting a device.

Users should also be vigilant in relation to email and not open any links or download attachments in emails from unfamiliar or possibly suspicious sources.

Experts warn that software, apps and other programs should never be downloaded from unofficial sources as this is another common method for hackers to secretly install malware onto computers.

Pete Turner, from cyber security firm Avast, said: “It’s critical that organisations and employees, particularly those in our most critical sectors like healthcare, start to think pro-actively about how to protect themselves from ransomware.”

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