![COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center](https://support.arduino.cc/hc/article_attachments/360016531980/COM_port_changes_3.png)
COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center
![COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center](https://support.arduino.cc/hc/article_attachments/360016532020/COM_port_changes_0.png)
COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center
![COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center](https://support.arduino.cc/hc/article_attachments/360016532000/COM_port_changes_2.png)
COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center
![COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center COM port number changes when connecting board on different ports or in bootloader mode – Arduino Help Center](https://support.arduino.cc/hc/article_attachments/360016532060/COM_port_changes_4.png)