You want to replace the bootloader. Perhaps you can’t get the board to upload programs and suspect the bootloader is not working. Or you want to replace an old bootloader with one with higher performance or different features.

Connect a programmer and select it as discussed in Recipe 18.12. Double check you have the correct board selected and click “Burn Bootloader” from the Tools menu.

A message will appear in the IDE saying “Burning bootloader to I/O board (this may take a minute)…” Programmers with status lights should indicate that the bootloader is being written to the board. You should see the LED connected to pin 13 flash as the board is programmed (pin 13 happens to be connected to one of the ICSP signal pins). If all goes well, you should get a message saying “Done Loading Bootloader.”