Solution: Download the mobile assistant from the computer, turn off the mobile phone, and enter the fastboot mode.Connect the computer with the data cable and click Restore the latest stable system on the mobile assistant page. fastboot,English translation means quick start.In Android phones, fastboot is a lower level flash mode than recovery.It is a flash mode that uses USB data cable to connect mobile phones.Compared with some system (such as ios) card brushes, wire brushes are more reliable and safe.
The driver may not be installed. First connect your mobile phone to the computer, then download a driver and check the driver. After checking, there should be an external USB driver not installed. Click Repair.