f.lux appears to be holding COM ports open in some situations
This is a strange issue, and it took some digging to pin the issue on f.lux.
Apparently, in some situations, f.lux is holding COM/USB Serial ports open even when none of the connected devices options are enabled.
I recently purchased a few Arduino Nano's development boards which have CH340G USB chips on them. When I try to program them using the PlatformIO development platform, I get an error unless I quit f.lux entirely:
avrdude: ser_open(): can't open device "\\.\COM7": Access is denied.
I'm not sure why this is happening because the Arduino IDE is able to program the device while f.lux is running, but I figured I'd share what I've found and see if there's any chance this is a previously unknown bug.
EDIT: Oh, I'm running 4.120, by the way. Let me know if there are other things I can share to help.
Thanks for the help,
Nevermind! I spoke too soon. The issue was with a piece of anti-malware software. Sorry for the bother..