How To Turn On Firewall (Windows and Apple)

For Windows:

1) Select the Start  button > Settings  > Update & Security  > Windows Security and then Firewall & network protection. Open Windows Security settings.

2) Select a network profile: Domain network, Private network, or Public network. 

3) Under Microsoft Defender Firewall, switch the setting to On. If your device is connected to a network, network policy settings might prevent you from completing these steps. For more info, contact your administrator. 

4) To turn it off, switch the setting to Off. Turning off Microsoft Defender Firewall could make your device (and network, if you have one) more vulnerable to unauthorized access. If there's an app you need to use that's being blocked, you can allow it through the firewall, instead of turning the firewall off. 

Note: If you get errors, or if the setting won't turn on, you can use the troubleshooter and then try again. 

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For Apple:

1) On your Mac, choose Apple menu > System Preferences, click Security & Privacy , then click Firewall. If the lock at the bottom left is locked , click it to unlock the preference pane.

2) Click Firewall Options. If the Firewall Options button is disabled, first click Turn On Firewall to turn on the firewall for your Mac.

3) Click the Add button under the list of services, then select the services or apps you want to add. After an app is added, click its up and down arrows  to allow or block connections through the firewall. Blocking an app’s access through the firewall could interfere with or affect the performance of the app or other software that may depend on it.

When your Mac detects an attempt to connect to an app you haven’t added to the list and given access to, an alert message appears asking if you want to allow or deny the connection over the network or internet. Until you take action, the message remains, and any attempts to connect to the app are denied.