I got a tablet from a friend. It's a Nexus 7 running Android 6.0.1. The first thing I did was reset to factory settings. After setting up, I saw there was an update to install. But it won't install.
Currently going to "System Updates" in settings shows "Android System Update Downloaded and verified..." and states, "This software update will improve the security of your Nexus 7 with the February 2016 patches. Downloading updates over a mobile network or while roaming may cause additional charges." And also, "Update size: 1.5 MB".
When I tap "RESTART & INSTALL", that button changes to "CANCEL INSTALL" and I see "Rebooting to install in 10 seconds..." which counts down. Then it shows, "Rebooting now..." but nothing happens.
If I wait for the screen to turn off, and press the lock button to light up the screen, I see it hasn't shut down. Unlocking it I find the screen with the "RESTART & INSTALL" button just as if I didn't tap it already.
I'm completely new to Android (though I am a Linux sysadmin if that matters or helps).
How can I get the update installed? Alternatively, is this even something to worry about?
Googling around turned up nothing useful, although I did find a forum thread from 2012 showing a similar issue with 4.2.1—but no solution.
(Note that as I'm completely new to Android, if there is some "default" advice I should know about such as there is for Mac, "if you can't figure it out take it to the Genius Bar," then please tell me as I don't know it.)