For those of you that have been getting stuck in a bootloop even after using the unbrick method, I found an earlier post by a fellow member that will help you out.
Or you can follow this youtube video...
MS770 - Factory Reset - YouTube
Flash your firmware again and let it finish 100%, reboot etc. Then yank the battery, and do a factory reset with the (I think the power, volume down, then tap the home and back keys simultaneously), and let it recover and it will get you out of the bootloop after the process is done.
Or you can follow this youtube video...
MS770 - Factory Reset - YouTube