1) Disconnect Ruijie authentication, shut down and restart, and then re-authenticate; 2) automatically obtain the IP address: the following operation process: right-click "Network Neighborhood" and "Properties"-> double-click "Local Area Connection"-> Properties->; This connection uses the following items. Double-click Internet Protocol (TCP/IP) in the drop-down box. Select "automatically obtain IP address" and "automatically obtain DNS server address" 3) reinstall the network card driver or reinstall the system; Use the elimination method to determine whether it is a personal system problem or a network problem within the port range. If all computers under its port have this problem, please report it to the operation and maintenance center for repair.