When the Android device is connected to the computer via USB cable,  the computer may not able to recognize the Android device or failed to connect to the Android device via USB cable. 

Please try the following guide:

1. Go to the developer option of your Android device to confirm whether  [USB debugging] is turned on.

2. Go to the developer options of the Android device, click [Revoke USB debugging authorizations - OK], then re-connect the USB cable and a pop-up windown [Allow USB debugging?] will appear. Please select [Always allow from this computer] and tap [OK].

3.  Switch the USB connection mode, different manufacturers will have different ways to switch the USB connection mode.

• For Android 8.0 and above: please set the USB mode to Charge Only (otherwise, the non-root will get failure after disconnect the USB cable)

• For Android 8.0 below: please set the USB mode to MTP

4.Use another USB port of the computer or replace another USB cable.

5. Restart the computer and Android device.