This setting on your Windows computer can protect you from hackers

As our Which? Tech Support team knows all too well, ransomware is one of the nastiest online threats facing Windows users.

This type of malware is designed to lock you out of your files by encrypting them, before demanding a ransom to restore access. It can target the files you care about the most – think family photos, important documents, work files and more. Plus there's no guarantee paying the ransom will restore access to your files.

To help protect against ransomware, Windows 11 and Windows 10 include a feature called Controlled folder access. It isn't always enabled by default, so it's worth checking your settings. Once switched on, it helps prevent untrusted apps from making changes to your important files.

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How to turn on Windows ransomware protection

Controlled folder access is part of the Windows Security app. As it isn't enabled on every PC by default, it's worth taking a couple of minutes to check whether it's switched on.

To enable Controlled folder access, do this:

1. Open Settings, then choose Privacy & security > Windows Security > Virus & threat protection.
2. Scroll down to Ransomware protection and select Manage ransomware protection.
3. Turn Controlled folder access on and, if prompted, approve the change using User Account Control.

What does Controlled folder access do?

Once enabled, Controlled folder access helps protect files stored in folders such as Documents, Pictures, Videos, Music and Desktop by blocking untrusted apps from making changes to them.

While antivirus software aims to detect and remove malicious programs before they can cause damage, Controlled folder access protects your files even if ransomware makes its way onto your PC.

This feature won't stop every cyber attack, but it adds an extra layer of protection against ransomware by helping to prevent unauthorised changes to your files.

Combined with good online security habits (more on that below), it's a simple and quick way to better protect your data.

Why isn't it enabled by default?

Controlled folder access can occasionally block legitimate apps from making changes to protected folders. Leaving it switched off initially helps avoid trusted software unexpectedly being unable to save or edit files.

If an app you use is blocked after switching the feature on, you can simply add it to the allowed list in Windows Security. That means you can continue using the software while still benefiting from the extra protection against ransomware.

Discover the best free antivirus and the best paid-for antivirus that will keep you safe from viruses and phishing attacks.

Other ways to secure your data

• Keep Windows up to date – Windows security updates fix vulnerabilities that hackers can exploit. Turning on automatic updates or regularly checking for new ones is one of the simplest ways to keep your PC protected. Head to Settings > Windows Update (Windows 11) or Update & Security and select Check for updates. (Still using Windows 10? Find out about Windows 10 losing security support.)
• Back up your important files – Even with ransomware protection enabled, it's worth keeping copies of your important files elsewhere. A cloud storage service or external hard drive can help you recover your photos, documents and other data if something goes wrong. See also: How to back up important files.
• Use strong, unique passwords – Avoid reusing passwords across multiple accounts, as a single data breach could put several logins at risk. If remembering lots of passwords is difficult, consider using a password manager to generate and store secure passwords for you. See also: How to create secure passwords.
• Turn on two-factor authentication (2FA) - Adding a second verification step makes it much harder for someone else to access your online accounts, even if they discover your password. We recommend enabling 2FA on important accounts such as your email, cloud storage and online banking wherever it's available. See also: Apps you need to secure right away.

Strange behaviour on your Windows or Mac PC could be more than a glitch, so check our advice on signs your computer has been hacked.

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