Hi guys, I just bought an unlocked M8 off amazon, good phone, great condition. I previously had an m7. I saw that marshmallow is out and checked to see if an update was available, phone said none available (up to date). Go to HTC and see there is an update for the unlocked version to Ver 6.12.1540.4 phone currently on Ver 4.21.512.5 Downloaded the RUU run it and get Error 132 Signature error. Any help would be greatly appreciated.