There is something wrong with the dial-up protocol of win8, so it is impossible to connect to the network (126720). Both desktop computer win7 and notebook computer win7 can surf the Internet normally. See the picture. When the telecom Tianyi wireless network card is used on win8, it often works normally and suddenly can't be used for one day. "Dialing protocol failure, code 126720" occurred during connection. I'm on my way. I've also encountered this problem. Asked a lot of people, Baidu has no solution. Many people stop here, don't need it, or switch to win7. However, it is more troublesome to change the system, which will lead to the unavailability of the C disk file. I am an obsessive-compulsive disorder, and I won't stop until I finish it. After more than a day of research, I finally found a solution. I think everyone has a headache, so I enjoy it. According to the following method, the illustration is simple.

1. Open the control panel, enter "System Restore" in the search box, as shown below, and then select "System".

2. Then the following dialog box appears, and select "System Protection".

3. The following dialog box appears, and select "System Restore".

4. Select "Select another restore point" in the next dialog box, and then click "Next".

5. At the most critical moment. First of all, you have to determine the time when your network card went wrong, and choose the most recent event before this day. For example, if something happens on the 28th, I will choose the 27th. If you have a problem for a long time before you see my method, then click "Show more restore points" (all fools know, haha). After selecting, click Next to start the recovery. About 5- 10 minutes. Make sure there is enough power.

6. After automatic restart, you're done. Run the client again (if the client is gone, please reinstall it) and you can connect normally. Tired of writing shit, I finally got it. Don't forget to thank me