Nexus 9 upgrade to Nougat fails - how can I diagnose the problem? I'm trying to OTA upgrade a Nexus 9 tablet running 5.0.1 to Nougat. I download the update, verify, and tell it to install. After a little bit, I get the "dead robot" screen that says "Error". 

I did a factory reset, downloaded the update again, ran it again, and got the dead robot again. 

I've been googling, but I can't find anything offhand that explains what might be happening.

Is there any way I can debug or diagnose the problem?
Well if you've already done a factory reset then I assume there's no precious data to be backed up on the device - in that case just grab a factory image, install appropriate drivers and flash manually. The one for the WiFi variant is already out.