Do not plug or unplug any charger into the car while it is doing a SW Update. Weekend before last, I was about to return from KC and decided to top off the X for the final stretch home at one of the KCPL's chademo chargers. There was a Leaf charging, so while I was waiting, I decided to do the SW Update which was available. The car reboots, but it's still updating when the Leaf owner finishes charging, and I decide to plug mine in. Plugged in the chademo after activating the charger, it starts but stops in < 10 seconds with the message "Car stopped charging". I return to the drivers seat to see the car has rebooted. Both screens come back, but both are completely unresponsive. Long story short, talk to Tesla Service Center (this was the day AT&T had the massive outage), they can't get the car to respond. Car doesn't reboot using either scroll wheel or the buttons above scroll wheels. Can't switch to drive, doors don't autoclose, A/C is off. About 45m into the call with Service Center, they advise me that I should call the roadside support who will try a 12v battery reboot, and if all else fails they'll tow the X to the Service Center where they have a loaner S waiting for me. As I am being informed of this, the X starts up. Looking at the logs later, it appears that the car was doing self diagnostics followed by finishing the SW Update. After that everything worked fine, and the Service Center OK'd the car as working fine and couldn't see any warnings. Been a week now, and all is fine. The Service Center told me that I shouldn't do anything to the car while the software is updating. They've had people try and do updates while driving, which is a definite NO-NO.