My Beaglebone Black refuses to boot. I have attempted booting as standalone, standalone with microSD, and connecting via PC. The LEDs turn on and there is activity, however, it seems stuck in boot. This is a brand new, out of the box Beaglebone Black.
some ideas to try,
do you have a usb-serial to connect to the BBB, if so, post your serial console boot log
are you powering via usb, if so, can you use a powered USB hub
when booting from the sdcard, hole the S2 button while connecting power