The Problem with Automatic Connections
macOS is designed to be helpful. By default, it remembers the password for every single Wi-Fi network you have ever connected to, and it will aggressively try to reconnect to them if they are within range. While this is great for your home network, it is infuriating in public spaces. If you once connected to a ridiculously slow, unreliable “Free Airport Wi-Fi” network three years ago, your Mac will stubbornly attempt to connect to it every time you walk through that terminal, dropping your fast cellular hotspot connection in the process. To stop this behavior, you must explicitly instruct your Mac to forget the bad network.
How to “Forget” a Network in macOS System Settings
You can manage your saved network database from the primary Wi-Fi settings panel.
- Click the Apple Logo in the top left corner of your screen.
- Select System Settings… (or System Preferences on older macOS versions).
- In the left-hand sidebar, click on Wi-Fi.
- Scroll down to the bottom of the right-hand panel and click the Advanced… button.
- You will see a section titled “Known Networks.” This is a master list of every router your Mac has ever memorized.
- Scroll through the list and locate the offending Wi-Fi network (e.g., “Airport Free Web” or “Starbucks Guest”).
- Click the circle icon with three dots (…) next to the network name.
- Select Remove From List (or “Forget This Network”).
- Click the blue Remove button to confirm.
What Actually Happens?
The Mac instantly deletes the network’s password from your secure Keychain and removes the SSID from its priority list. The next time you are physically near that router, your Mac will see the signal, but it will treat it as a completely unknown, foreign network. It will absolutely refuse to connect to it automatically, ensuring you remain securely connected to your preferred network or hotspot without interruption.