Hi, although I've been building a variety of Arduino projects, with different types of Arduino boards for a few years now, I've never posted anything to the forum before. Hopefully I've picked the right community, etc...
For the last 6 months or so, whenever I try uploading code to a Pro-Mini board, and even a Pro-Micro, I struggle with the following error message (not always the same port number):
"avrdude: ser_open(): can't open device "\.\COM2": The system cannot find the file specified."
Prior to getting this error, I am often able to upload the code, but once this error shows up, nothing much seems to work to eliminate it (other than one thing - see below).
Let me say that I know this topic has been discussed before over the last few years, and I've read all the posts and replies I can get my hands on, and I've tried all of the "fixes", but so far NOTHING seems to work reliably.
I am running Windows 11, and Arduino IDE Ver2.2.1.
I have spent days trying all of the following, without any luck:
- Restarting the computer (until I'm blue in the face). This is a huge time waster.
- Different computer
- Restarting the IDE
- Multiple different USB cables, all of which work fine for anything else - and for this sometimes
- Two different Sparkfun FTD boards (when using the Pro-Mini)
- Different USB outlets
- Different Arduino boards
- Different Arduino sketches
- Selecting different ports
- Adding a capacitor from the DTR pin to the RST pin. It turns out my Pro-Mini boards already have a cap between those pins, and a 10k pullup on RST, so adding one does nothing.
Yes, I've selected the correct board and the correct port in the IDE. I've tried suggestions such as uploading the code without the board plugged in, deleting the error message first (I don't know why this would ever work), and selecting a different port - making sure it's not already in use.
The ONLY thing the has seemed to help get around this error is to go into the device manager, select the port being used, and change some of the Advanced settings, such as Latency Timer. After changing a setting and saving it, I am often able to upload a program once or twice, and then the error returns! The point is that there is no setting I've found the reliably eliminates the error.
Interestingly, I don't remember EVER having this problem a year or two ago, which makes me think this problem may be related to a newer version of the IDE.
Any help would be much appreciated.
Thanks!