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Active6 months ago
If you get the following error: can't open device 'COM10': The system cannot find. Over from other USB devices, you can simply change the COM port using the.
I went to upload my sketch to my Uno (r3), but unusually, the Upload Console returned this error:
![Device Device](/uploads/1/2/5/6/125607223/717882568.png)
Just started seeing this, cannot upload.
Avamander60022 gold badges99 silver badges3434 bronze badges
samiles1995samiles1995
3 Answers
There might be another device has already connected to that port. It could even be a terminal emulator which is left connected from last debugging session.
Otherwise, make sure that your UNO is really presented on COM4 by checking with 'Device Manager'. if not, change the port where it is available.
SenerSener
You have selected the wrong COM port. Go to Tools -> Port -> Select the right port. If you do not know the port number disconnect the Arduino, open the same menu again and look what is listed there, write down if you can't remember, now plug your Arduino back in and select the option that wasn't there before.
AvamanderAvamander60022 gold badges99 silver badges3434 bronze badges
I'm using a windows 10 and had this happen randomly. I closed several other applications and it started working again.
cagneycagney