Reasons and solutions for not being able to connect to the Internet after being connected to the network:
(1) There may be a DNS error that prevents internet access.
(2) There may be an ARP virus in the LAN. It leads to network blocking and inability to access the Internet.
（2） Treatment method:
(1) The first reason is to fill in DNS again. The specific steps are as follows:
1. Open the "run" dialog box (or press Win + R), enter the command "CMD" to enter the MSDOS interface.
2. Enter the command "ipconfig / all" in MSDOS interface, and the local gateway and DNS information can be viewed in the displayed result page.
3. Open control panel, double-click network connection, then right-click local connection and select properties.
4. Check "manually set DNS" to set DNS for the current connection. After setting, check whether you can surf the Internet normally again.
(2) The processing method for the second reason: it can be completed by static binding ARP operation. The specific steps are as follows:
1. Install 360 security guard on the computer, open 360 security guard, select "360 Trojan firewall" in "complete functions", click enable ARP firewall, and click OK in the pop-up prompt dialog box. Then restart the computer.
2. After the computer restarts, 360 security guard will remind that ARP protection is successful. Click on the details, you can intuitively see the communication situation of the network. So far, the computer can surf the Internet normally and safely