Sunshine has been the method to unlock the bootloader of many HTC devices and even a few Motorola devices. The app does require you to be rooted or at the very least temp rooted. Some of you who updated your Verizon HTC One M8 have been locked out of unlocking your bootloader since there has not been a method for temp rooting. As it turns out KingRoot may very well be able to temp root your device. A user is reporting on XDA that he was able to use KingRoot to temp root his phone, and then use Sunshine to get S-off. The method listed is a 20 step semi tedious process, but it is a process that anyone can do. There are no intimidating command prompts or anything here. Head to the link below for the full guide and necessary download links.
via XDA