Firewall is on and configured
Firewall prevents contact from other computers on the Internet or on your network. Learn more on the Apple Support page.
What if I use other firewalls?
You should have the system firewall enabled because other firewalls cannot support stealth mode. Stealth mode is necessary if you are directly connected to the internet via a hotspot or without a router, for example. Stealth mode prevents your Mac from being discovered by threat actors scanning the internet for devices.
Time to fix
How to enable Firewall and Stealth mode
- Open System Preferences, click Network, then Firewall.
- Toggle Turn On Firewall.
- Click Options..., scroll to the bottom, and toggle Enable stealth mode.
How to enable on Monterey and older
- Open System Preferences, click Security & Privacy, then the tab Firewall.
- Click the lock icon in the bottom-left, then enter the account password.
- Click Turn On Firewall.
- Click Firewall Options... and then Enable stealth mode.