पिछले पासवर्ड की वजह से वाई-फाई नेटवर्क से कनेक्ट करने में असमर्थ होने पर आप क्या करते हैं?

My brother changed the password for the Wi-Fi network I use to connect my laptop to the Internet when he moved to another city. I know the new password, but I am unable to connect to the Internet now because of the previously saved password.

How can I remove the old password and add the new one?

The best way would be to delete or “forget” the network and connect to it fresh. To delete a wireless network connection in Windows 7:

1. Open the Network and Sharing Center.
2. In the Tasks Pane, click Manage Wireless Networks.
3. Right-click on the connection you want to delete, and then click Remove Network.
4. In the Manage Wireless Networks – Warning Dialog Box, click OK.

Source: Delete a Network Connection in Windows 7 and Windows Server 2008 R2 [TechNet – Microsoft]