My Net N750 unresponsive after firmware update

Thanks for the recommendation, but this is does nothing.  I’ve held the reset down manually from 10 seconds up-to a minute on and off for the last few days.  The power led still flashes blue.  It just seems to be stuck in the boot up.  I’ve left it plugged in over night with ethernet running to it, and without ethernet running and both times, same issue.