If you're not sure if your computers are up to date, then open the Control Panel (you'll find a link in the Start menu) and search for Windows Update. Click through to Windows Update and you'll be able to check if it's enabled or not.
There should be a button 'Check for updates' which you can click to force Windows to search and install critical updates.
But don't stop there, sit back and consider you're safe. Follow our advice to keep your files safe from ransomware.
The best protection is to have at least one (if not two) copies of any files you can't afford to lose. Photos, home videos, financial documents and other files that can't be replaced should be backed up regularly.
Ransomware is often clever enough to scan your home network and infect other computers and even network storage drives (NAS drives) so it's really important to make a backup on a USB stick or external hard drive that you disconnect and keep safely somewhere.
You can find our pick of the best backup software here.
Don't open attachments
You, as the computer user, are often the weak link in the chain. Windows and antivirus software - see below - can help to protect you from ransomware attacks, but you can help yourself by being vigilant about which email attachments you open, which links you click and which downloaded files you run.
Typically, emails from hackers won't contain a personal message, or it will be so generic that you can't be sure it's really from the person in the 'sender' field.
In WannaCry's case, at least some of the emails pretended to be an important email from a bank about a money transfer.
Either just delete the email, or call the sender and ask them if they sent the email and what is in the attachment, or on the other end of the link. Unless you are absolutely sure the attachment is safe, don't click on it.
Won't antivirus software protect me from ransomware?
Most but not all antivirus software now contains 'anti-ransomware' that should help protect your PCs and laptops from WannaCry and other ransomware.
That's why it's important not to rely just on Windows' own security but to add an extra layer of protection.
My PC is infected with ransomware. What should I do?
First, don't pay the ransom. It only encourages the criminals - getting paid is their end game. And there's no guarantee you will get your files back even if you do pay.
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