I plugged a USB cable (connected to an Arduino Nano clone) into my MacBook Pro (running OS X 10.11.2) and it crashed with an on screen message.
It restarted and reloaded all my apps (eventually).
It seemed to be working normally, so I tried the Arduino again, with similar results.
Console shows a very long list of messages. The first which seems possible is:
6/01/2016 11:43:39.355 AM mdworker: LaunchServices: received XPC_ERROR_CONNECTION_INTERRUPTED trying to map database
Additional notes The Arduino required an additional driver which I installed a week ago (CH34X USB-SERIAL DRIVER). This seemed to be working OK.
Can anyone help with this. What can I check? (I can certainly live without the Arduino.)