Changes

*Wrong COM port selected : People occasionally select the incorrect COM port. Each computer has a unique COM port number, and you must select the correct one for your computer.

*Wrong COM port selected : People occasionally select the incorrect COM port. Each computer has a unique COM port number, and you must select the correct one for your computer.

*Selected wrong board at tools menu : You have to select the correct board option. For instance, if you choose Arduino Nano for Arduino Uno, your code will upload.

*Selected wrong board at tools menu : You have to select the correct board option. For instance, if you choose Arduino Nano for Arduino Uno, your code will not upload.

*Defective USB port : Connect your Arduino board to a good USB port on your computer and check for physical flaws in the USB port on the Arduino board. Connect to a different USB port on your computer.

*Defective USB port : Connect your Arduino board to a good USB port on your computer and check for physical flaws in the USB port on the Arduino board. Connect to a different USB port on your computer.

*Inspect for physical damages on Arduino board : Microcontrollers or other passive or active components may have flaws that are not physically inspectable or changeable; in this case, replace the entire board.

*Inspect for physical damages on Arduino board : Microcontrollers or other passive or active components may have flaws that are not physically inspectable or changeable; in this case, replace the entire board.

To fix some other problems, try Reinstall the Arduino IDE or try to upload a sketch from another computer

To fix some other problems, try Reinstall the Arduino IDE or try to upload a sketch from another computer