Problem with uploading to UNO using Windows 10


I am having problem with the upload of the sketch. The error i am getting is

avrdude: ser_open(): can't set com-state for "\.\COM9"
An error occurred while uploading the sketch

Any help appreciated, thanks.

Make sure you have selected the port of your Arduino board from the Arduino IDE's Tools > Port menu. It might be that the COM9 port you have selected is some other device on your computer.

Sometimes the port will be labeled with the board name in the menu. Other times it will not. If you don’t know which port is your Arduino board, you can find it like this:

  1. Unplug your Arduino board from the computer.
  2. Select Tools > Port from the Arduino IDE's menus.
  3. Note the ports, if any, listed in the menu.
  4. Close the Tools menu. The ports list is only updated when the Tools menu is re-opened, so this step is essential.
  5. Plug your Arduino board into the computer.
  6. Select Tools > Port from the Arduino IDE's menus. - The new port listed in the menu is your Arduino board.
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What's your Arduino board? Give please a link or good photo of both sides.
What does your Device Manager show when you plug the board into a USB port on your computer?

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