Can't connect to NV+ after 4.1.14 upgrade

I'm also unable to connect to mine, but that's because it's been in "Booting ..." according to the LCD display for about 5 hours now. (this was after an automatic download of the 4.1.14 firmware, followed by a "shutdown and reboot" from Frontview.) No other errors or alerts via email at any time in this calendar year (replaced a bad drive in 2013, but otherwise this system just runs). I'm nervous about yanking power during a boot, but I'm not sure what else I can do - holding down the power button on the front (either short-term to get a graceful shutdown, or 10+ seconds to get immediate power-off) has no effect at all.