Flash !full! Download Upd Tool 392 -

Try a different USB port (preferably on the back of the motherboard if using a desktop) or update your COM port drivers.

The (specifically version 3.9.2 and later) is the official utility from Espressif Systems used to flash firmware onto ESP32, ESP8266, and ESP32-S/C series chips. Step 1: Download & Preparation flash download upd tool 392