Error updating model 100 factory firmware: dfu-util exit 74

I am unable to update firmware on a new model 100. I get an “error updating firmware” message in chrysalis and looking at the developer console I see dfu-util exited abnormally with an error code of 74. I checked the dfu-util source code for exit code 74 and it’s # define EX_IOERR 74 /* input/output error */ so probably some fairly generic error communicating with the keyboard over USB.

I have tried both the instructions in the chrysalis GUI (hold PROG for start of update process) as well as the variation described in this forum post (hold PROG before plugging in USB).

I have tried rebooting and updating my arch packages. This error happens consistently. I am able to change and save my keymap though and the model 100 does work properly as a keyboard both halves.

OS: arch linux (kernel 6.1.1-arch1-1 #1 SMP PREEMPT_DYNAMIC x86_64)
Chrysalis: 0.12.0
Firmware attempting to flash: 0.90.1

That sounds like a permissions problem that’s fairly common on Linux. Try installing the udev rules from Chrysalis/60-kaleidoscope.rules at master · keyboardio/Chrysalis · GitHub

Chrysalis should detect the permissions problem and offer to install the udev rules, but it doesn’t always.

That fixed it. Thanks so much! I also did a udevadm control --reload and next time I launched chrysalis I saw a message in the bottom right that a model 100 was recognized that was not there before.