'Forget' or remove a wireless network from your Mac so it no longer connects to that network automatically.
- Click the Apple menu and then System Preferences, then click Network.
- Select Wi-Fi in the list on the left.
- Click the Advanced button.
- The Wi-Fi pane shows a Preferred Networks list. Select the Wi-Fi network that you want your Mac to forget.
- Click the remove button (–) beneath the list. If you're asked to confirm, click Remove.
- Click OK.
- Click Apply.