How to allow or block programs with the Windows Firewall - Which? (2024)

If you're not sure whether to allow a program through your firewall, follow our handy guide to help you make the right decision

Tom MorganSenior content writer

The Windows firewall works like a filter between your PC and the internet, blocking or allowing connections depending on whether or not they’re safe.

Firewalls will block or allow a lot of traffic automatically, but sometimes you will see a message asking you if you want to allow a program to connect to the internet. This usually happens when you use a new program for the first time.There could also be situations where you need to allow a program through your firewall that has been blocked incorrectly.

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Below, our tech experts explain how to use Windows Firewall.

How do I allow a program through the Windows Firewall?

To manage the 'allow' list for Windows Firewall, select Start, type Allow an app or feature through Windows Firewall, then click it.

On the next screen, choose Change settings, then tick or untick the box next to an item to allow or block it.

Alternatively, you can tick or untick the box in either the Privateor Publiccolumns. This is for if you wanted to allow a program internet access when you’re connected to your home network (Private), but blocked when you’re connected to a public one, such as a wi-fi hotspot.

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Block all incoming programs

There are occasions where it’s much safer to block all incoming data connections to your computer, including all of the programs on your ‘allow’ list.

For example, you may wish to do this if you’re using an unsecured wi-fi connection that you don't trust.

To disallow all incoming data connections with the Windows Firewall, select Start, type firewalland choose Windows Firewall > Change notification settings.

Under Public network settings, untick Notify me when Windows Defender Firewall blocks a new app, select Block all incoming connections, including those in the list of allowed programs, then OK.

With this setting enabled, you’ll still be able to send and receive email and browse the web, but other connections will be blocked automatically.

Just make sure you remember to undo the changes when you return home.

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