1. In the Windows 7 system we clicked on the "Wireless Network icon" on the taskbar and then we clicked on the Open Network and Sharing Center on the opening screen as shown in the picture.
2. Then we click to open the "Network Sharing Center window" and there is a "manage wireless network" on the left and then we click again.
3. It will then show all the wireless networks that have been successfully connected to the current computer, select the network that is not currently connected, and then click the "Remove Network" option.
4. Then click "Yes" in the pop-up prompt confirmation box to remove the WLAN network that I can't connect to.
5. After removing the good wireless network, we need to connect again, then click on the wireless network connection list, click the wireless network that cannot join before.
6. Then we'll re-enter the WiFi username and password.