Yup, if you recovery flashed an older firmware over 4.3, insta-brick!
To know for sure plug into the computer and open device manager. If you see QHSUSB_DLOAD, its bricked and your only hope of fixing for free is the debrick thread as serio22 said.
Shortly after the USA Unlocked and Developer Editions of the HTC One M8 received the … more
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