Windows 10 Device Manager fails to recognize UNO


I am new to Arduino, so please be patient. I have purchased the starter kit, downloaded & installed the Arduino IDE software and plugged the UNO board into the USB port. The instructions say that the driver should be automatically downloaded because I am running windows 10. But when I go to the device manager, the port is registered as "USB Serial Device (COM3)." There is no Other Device/Unknown Device listed in the Device Manager. I can only assume that the UNO board has not been recognized so the driver has not downloaded. There is one other thing - the green ON light is flashing on the UNO board, but there is also a yellow light flashing. The yellow light is labelled "L" and is immediately below a painted label entitled "Digital - PWM~".

Have I done something wrong, or is there something wrong with the UNO board?



Yes, COM3 does disappear. That tells me the the laptop knows there is a device connected to the USB port, but for some reason it cannot recognize what it is. The flashing yellow light on the UNO board may be further proof, but I am not sure as this is the first time I have plugged an Arduino board into a computer. Any thoughts?

Is this a clone board? Those will always identify as a USB-serial interface, because that's what they have. The official boards have a 16u2 running firmware that makes it act as a USB-serial interface, but they also show up as Arduino Uno (or whatever) in the device manager. But yeah, nothing you've described thus far indicates a problem.

Try uploading a sketch to it.


I would be surprised if the board is a clone, we got it by purchasing the Arduino Starter Kit on Amazon. Attached is a pdf photo of the plugged-in board, complete with flashing yellow light. DrAzzy said nothing seems wrong, so we will try the first experiment in the starter kit and see what happens. Thanks for the help, I will let you know what happens!!

UNO Board.pdf (1.02 MB)

Looks identical to mine, part of a large Elegoo kit.

I'm new to Arduino and keep hearing this word 'clone' in the context of something inferior? But my understanding is that my 'Arduino/Genuino Uno' is, as its name implies, a genuine copy, identical to the 'official' boards?

Often the boards referred to as clones are not identical copies. The most common difference is the use of the cheaper CH340 USB to TTL serial adapter chip instead of the ATmega16U2 used on the official Arduino Uno and Mega. Those boards would be more correctly referred to as derivatives. The term "clone" does imply that the hardware is identical.

Even if you get a clone that is truly identical hardware-wise, there is still a significant difference. The difference is that part of the money spent on buying official Arduino boards goes to paying the salaries of the people who write the code and documentation all Arduino users benefit so much from, whether they are using an official, clone, derivative, compatible, or counterfeit board. Although this is an open source project that welcomes contributions from the community, I don't believe any of the clone manufacturers contribute at all, and it is very rare that any of the derivative or compatible board manufacturers contribute either (with a few notable exceptions like Paul Stoffregen of Teensy).

There is always the question of quality control and customer support with the unofficial boards as well. Especially with the impossibly cheap boards, some corners must be getting cut, whether that is in quality control, worker wages, environmental protection, etc. A high price is not always a guarantee of quality either. Who's to say the high price isn't just the result of a markup being charged by a middleman selling that same cheapo Chinese board?

Arduino boards are open source hardware. Arduino publishes their design files and allows anyone to make and sell their own boards based on those designs. Other manufacturers must not use Arduino's trademark to market their boards. The boards that do that are counterfeits. The open source license of Arduino's design files requires that anyone who makes changes to the design should also publish their design with the same license. Many of the derivative manufacturers don't comply with that requirement.

Thanks for the feedback everyone, it is much appreciated. I am going to run the first few projects with my daughter, to see if it works. I am not optimistic, the flashing yellow light is not a good sign.....I will let you know what happens. At least I can get my money back, as I purchased it through Amazon.

One last question (at least, for now). Can anyone recommend a reliable site where I can be sure to get the genuine article regards Arduino boards? My daughter seems really interested in this, we are taking our first steps, not our last.

the_alien_cat: the flashing yellow light is not a good sign.

That's incorrect. The "L" LED is connected to pin 13 of your Uno. It is normal for these boards to come running a program that blinks that LED. The first time you upload a sketch that doesn't blink the LED it will stop.

the_alien_cat: the green ON light is flashing on the UNO board

That one is worrisome. The power LED should not blink.

But regardless, just give it a try. It only takes a matter of seconds and you've spent much more than that already. Arduino is all about learning and experimentation. You need to have the courage and drive to just try things out.

the_alien_cat: Can anyone recommend a reliable site where I can be sure to get the genuine article regards Arduino boards?

You're certain to get genuine Arduino boards in the Arduino Store: If you like Amazon, Arduino has an official seller account there too: There are also many authorized distributors of Arduino products. If you purchase Arduino branded boards from any of these companies I think you'll be sure of getting the genuine article (but note they may also sell boards from other brands as well): Some of the official distributors also sell genuino Arduino boards on Amazon.

the_alien_cat: My daughter seems really interested in this, we are taking our first steps, not our last.

That's really great! I wish I had access to something like Arduino when I was younger.