1. First of all, rule out the question that many netizens on the Internet answer whether it is a router or a wireless gateway. Even if the phone can't find the network, it will display several default networks, such as ChinaNet, and will not automatically turn off.

2. In the past, when WLAN was turned on, three default networks, such as ChinaNet, and the saved list of wifi hotspots would pop up first, and new networks would be scanned at the same time. Now it is not displayed after being turned on.

3. After the self-check, all operations that may cause the problem before the problem occurs are basically ruled out, and there is no operation to modify system files or install new software.

4. Delete the operation. The conf file under data/misc/wifi mentioned by netizens has been tested and useless. This file records the default and saved WiFi hotspots, with only four records (my default is 3+1 router).

5. After deleting this file, directly testing and opening WLAN will prompt an error. Opening WLAN after restart will automatically generate a new file, which should be automatically copied from system/etc/wifi.

6. Restart, charge and connect the power supply. All illogical methods such as earphone connection and flight mode have been tested, and the results are bound to be invalid.

7. The mobile phone has not been dropped, so it should not be a hardware problem. Basically, it can be determined that it is a system problem. There is no attempt to restore the factory and brush the machine at present.

8. The mobile phone took root and succeeded. The system-related key function software has not been deleted, and everything is normal after root and slimming. This problem suddenly appeared after a few days of use, and it is normal to surf the Internet a few hours before the problem occurs.

9. Have you tried using WIFI? FIXER(WIFI repairer), the software doesn't understand and can't be used. After running the test, you will be prompted "None" when opening WLAN. Invalid? What about wifi? Disability

10. I will continue to try to find information. I don't want to refresh my computer or restore the factory settings unless I have to. However, if the problem cannot be solved continuously, an attempt will be made to follow up the follow-up situation. ?