During uploading a sketch this message "avrdude: ser_open(): can't open device "\.\COM1": The system cannot find the file specified." is often mentioned.
It happened also when I was uploading a sketch to an Arduino UNO which was connected to an USB-3 port of a Windows 11 laptop.
I saw in first instance that Tools-Port (Arduino-IDE) was greyed out.
After some trials I found that connecting the Arduino UNO to the USB-2 port of the laptop was the solution. I now could select an USB port with Tools-Port. Only COM4 was available. Problem solved.
Then after connecting an Arduino Nano to this USB-2 port of the Windows 11 laptop then COM1 and COM4 could be selected.
After connecting again an Arduino Uno to that USB-3 port now it became possible to select a COM port. In this case COM4 only.
Finally I connected an Arduino Nano to USB-3 and now COM1 or COM4 could be selected.
Obviously a Nano is less critical than an Uno.
Perhaps this experience may be useable/useful.
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