Win7 system has its own network detection function. If the system shows that the connection with the Internet has been disconnected, you should do the following:

First, if it is a public wireless router, check whether your laptop is set with the IP information of the wireless network card.

Second, if it is a private wireless router, check whether the network configuration of the wireless router is normal, or use another notebook to see if you can surf the Internet.

Third, if someone else's laptop is connected normally and your laptop is not, see if you are infected with a virus.

Fourth, the signal strength.

Fifth, in the management of wireless wired network, CERNET has been deleted, or there are too many AP information in it, and all the unused ones have been deleted. Try to connect again.

5. None of the above works, then reinstall your wireless network card driver. (Unload before installation)

Personal opinion, for reference only.