I'm trying to connect my Arduino Uno to the IDE, but it wont work. In the serial monitor it says "Could not connect to COM11 serial port". I tried different cables, an Arduino Nano, different ports, other IDE versions. When I tried it on a laptop it worked, but it's not working on my PC. Can someon…

Hi @gerardasst . Which version of Arduino IDE are you using (e.g., "2.0.1")? The version is shown on the window title bar and also in the Help > About (or Arduino IDE > About Arduino IDE for macOS users) dialog. I ask for this information because I want to give you the appropriate instructions for …

Hey @ptillisch , The Arduino IDE version i use is 2.2.1 and here is the error screenshot: [image]

OK, great. There were some previous reports of this "Port monitor error: command 'open' failed: Invalid serial port. Could not connect to COM3 serial port." error occurring specifically when Serial Monitor is opened in Arduino IDE while the port of a board that uses the WCH CH340 USB chip (and appar…

I tried the steps, but it says that the best drivers are already installed.

I'm going to ask you to provide some additional information that might help us to understand how to proceed. Please do this: Connect the Arduino board to your computer with a USB cable. Open the Windows Device Manager . Select View > Devices by type from the Device Manager menus. Open the "View" m…

Well I have some good news, it randomly started working. When I installed the drivers it didn't work, but I tried it a bit later and randomly started working.

I'm glad it is working now. Thanks for taking the time to post an update! Regards, Per

Cannot connect Arduino UNO to Arduino IDE

Development Tools IDE 2.x

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Cannot connect Arduino UNO to Arduino IDE

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