thanks for the fast response. Yes Windows7 pro, this the good driver
test with :

• another cable (in 115200 or 921600 baud ) : not ok
• another PC in Win10 and new install drivers + M5burner (in 115200 baud) : OK

i'm happy !

Hello everyone,
It's my first M5Stack,
after a flash with M5burn with a new M5GO with the 1.4.1.sg FW, its work fine with http://flow01.m5stack.com/ but i can't reflash (or Erase) with a older 1.4.0 FW :
can't connect with USB port (but USB31 is here)
The screen go black, it's beep every 1s, but nothing

Error message :

esptool.py v2.5.0
Serial port COM31
Connecting........_____....._____....._____....._____....._____....._____....._____

A fatal error occurred: Failed to connect to Espressif device: Invalid head of packet (0x30)
Finished

Any idea ?