When something goes wrong with your iPhone's wireless functions, such as when it can't connect to an active wireless network, you may need to forget or delete the network. In the process, relevant data such as Wi-Fi passwords and server settings will be removed. Here's how you do it:

1. Go to the main menu and select 'Home.'
2. Go to the Settings tab.
3. Toggle the button.
4. Tap Wi-Fi
5. Next to the Wi-Fi network, you want to delete, tap the blue I or information icon.
6. Select Forget this Network from the drop-down menu.

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