This means you missed the security pop-up on your tablet screen. Unplug the USB cable, plug it back in, and unlock your tablet screen. The prompt should reappear. If it does not, go to Developer Options on the tablet and tap Revoke USB debugging authorizations , then try again.
If you are connecting an A133 tablet or head unit to a Windows PC and it is not showing up in "This PC" or Device Manager shows "Unknown Device," you need the standard Android ADB/Interface drivers. allwinner a133 usb driver
If successfully installed, your command prompt will output a unique string of numbers followed by the word device . If it says unauthorized , look at your A133 tablet screen and accept the RSA fingerprint prompt. Troubleshooting Common Driver Issues This means you missed the security pop-up on
Open PhoenixSuit and load your target firmware image before plugging the device into the computer in FEL mode. Summary for Developers If it does not, go to Developer Options