Modifications

# Prepare the computer to show you a list of its virtual serial ports. If you are using Windows, this means you should open the Device Manager. If you are on Linux or Mac OS X, this means you should open a Terminal and type the command {{fname|ls /dev/tty*}} but do not press enter until the board is in bootloader mode in the next step.

# Prepare the computer to show you a list of its virtual serial ports. If you are using Windows, this means you should open the Device Manager. If you are on Linux or Mac OS X, this means you should open a Terminal and type the command {{fname|ls /dev/tty*}} but do not press enter until the board is in bootloader mode in the next step.

# Press the reset button twice within 750 ms to make the AVR go into bootloader mode. You should see the yellow LED fading in and out when the AVR is in bootloader mode. While it is in bootloader mode, quickly look at the list of serial ports provided by your operating system in order to determine what port the bootloader is assigned to.

# Press the reset button twice within 750 ms to make the AVR go into bootloader mode. You should see the yellow LED fading in and out when the AVR is in bootloader mode. While it is in bootloader mode, quickly look at the list of serial ports provided by your operating system in order to determine what port the bootloader is assigned to.

# Type the following command in your terminal and replace COM4 with the name of the bootloader’s serial port, but do not press enter yet. This command will erase the malfunctioning program on the device but preserve the bootloader.<br /><br /> <nowiki>avrdude -c avr109 -p atmega32U4 -P COM4 -e</nowiki>

# Type the following command in your terminal and replace COM4 with the name of the bootloader’s serial port, but do not press enter yet. This command will erase the malfunctioning program on the device but preserve the bootloader.<br />{{fname|avrdude -c avr109 -p atmega32U4 -P COM4 -e}}

# Press the reset button twice within 750 ms to make the AVR go into bootloader mode.

# Press the reset button twice within 750 ms to make the AVR go into bootloader mode.