Configuring the macOS Firewall


Upon opening Transmission for the first time, a macOS dialog box should appear asking if you will allow Transmission to receive incoming connections. Click Accept.

If this doesn't happen, you can add Transmission to the firewall manually:

  1. Open System Prefs → Security → Firewall. Make sure "Set access for specific services and applications" is selected.
  2. Click the "+" button and select Transmission from your Applications folder.
  3. Make sure the pull down menu is set to "Allow incoming connections".