I have a user who has had a working 8700R for 5 months. Now they report that the unit will not power on (2 days after they cratered the software load and I had to do a hard reset on the unit and reactivate over the network). I have tried another known good battery from another 8700R as well as using the suspect battery in a known good 8700R......Known good BB works with both batteries and the problem BB does not work with either battery. So we can eliminate the battery as the problem. I know that there is a setting for having the units only power on during a certain time frame like bussiness hours etc.....Will this stop the unit from powering on manually? Failing that it looks like a warranty claim for service unless anybody else can think of something else to try.

Sounds like you need to RMA it. Lots of things that could be wrong... Backlight gone out, bad system board, etc.