Unable to remove /reconfigure external keyboard configuration in System Preferences

Question

The external keyboard configuration from Preferences|Keyboard|Modifier Keys is not working properly on my Sierra mac. It works fine for the same and other external/USB keyboards on my two El Capitan machines.

The following http://rainer.4950.net/2009/09/30/resetting-the-usb-keyboard-type-on-mac-osx/ recommends to disconnect the external keyboard and then delete /Library/Preferences/com.apple.keyboardtype.plist.

However after having done so - and verified the file no longer exists:

$ls -l /Library/Preferences/com.apple.keyboardtype.plist
ls: /Library/Preferences/com.apple.keyboardtype.plist: No such file or directory

But the external keyboard still shows up:

I am trying to get back to the "Unrecognized keyboard" dialog - in the hopes of fixing key mapping problems only on this Sierra machine: specifically

The end goal is for the following to actually work properly: i.e. disabling caps-lock and swapping option and command.

Instead those customized settings are presently ignored and only the default mappings are actually enabled.

Answer 1

I found ignasi35's suggestion works as an answer to this question of how to reconfigure an external keyboard, that is:

1. Unplug external keyboard
2. Delete /Library/Preferences/com.apple.keyboardtype.plist
3. Reboot
4. Plug in external keyboard

In my specific situation my ` and § keys were swapped and reconfiguring did put them back.