You’ve been connected to a particular password-protected Wi-Fi network for some time already, and it has never stopped you from doing your online work—until now. An admin must have changed the network settings, and you’re no longer able to connect to it despite having learned of the new Wi-Fi password. Here’s how you can make your computer forget the old settings so you can use the new password.
If you have a computer running Windows 7, open Network and Sharing Center. To do so, right-click the network icon on the system tray or notification area of the taskbar and select Network and Sharing Center. Click Manage Wireless Networks, which is located at the left task pane. Select the wireless network profile that you’re no longer able to connect, click Remove, and confirm by clicking OK.
Once your computer has deleted its profile for that particular wireless network, join the network as you normally would. If you did everything right, you will be asked to type in the new Wi-Fi password and be able to connect again.
Forgetting a wireless network is easier on Windows 8 or 8.1. Simply left-click the network icon on the system tray of the task bar, right-click the problematic wireless network, and click Forget this network. Try connecting again and enter the new Wi-Fi password.
Other non-Windows wireless devices also tend to show an error message about not being able to connect (assuming they were able to do so before and had saved the connection settings) instead of prompting you to enter the new Wi-Fi password. When this happens, simply navigate to where your devices save their wireless settings and remove, erase or forget these settings before trying to connect to the network again. If you don’t know where to locate these settings, read the instructions from the user manuals.