Arduino uno r3 error on IDE 2.1.1

Using Arduino Avrdude, stk500, Bootloader issues
3

Hello

  1. Which operating system are you using?
  2. Which version of the IDE are you using?
  3. What is the TTL-to-USB converter on your board? It's the chip closest to the USB connector. Some possible option are Atmel 16U2, CH340 or FTDI.
  4. If your board is not using the CH340, what are the results of the loopback test?
  5. Is anything connected to pins 0 and 1 of the board?

Please explain; drivers reside on a PC, not on the Arduino.

See topic title :wink: