If the automated process keeps hitting an error (like Error -1 or Error 53), Pro Flash provides the detail needed to see exactly which component is failing.
The device will reboot. You will see a progress bar on the phone screen and a percentage tracker in 3uTools. Do not disconnect the device or use the computer for other heavy tasks during this time. pro flash 3utools
Always ensure you have a stable MFi-certified cable and a high-speed USB port when using Pro Flash; since it handles higher data volumes across potentially multiple devices, a loose connection can lead to a "bricked" state that requires a DFU restore to fix. If the automated process keeps hitting an error