Is your phone UNLOCKED ? If yes .. then install TWRP then restore 6.16.401.101 backup from here : http://forum.xda-developers.com/htc-one-m8/help/tutorial-how-to-stock-stock-twrp-t3086860Hi. I followed this thread and felt my problem is very much similar. I hope I am right. Phone does not go past the start-up screen after the OTA Update. The Phone is a dual sim phone. I would greatly appreciate your help here. This following is the output from the fastboot getvar all
(bootloader) version-bootloader: 3.19.0.0000
(bootloader) version-baseband: 1.24.30336021.13G
(bootloader) version-main: 6.16.401.101
(bootloader) version-misc: PVT SHIP S-ON
(bootloader) product: m8_dugl
(bootloader) platform: hTCBmsm8974
(bootloader) modelid: 0P6B64000
(bootloader) cidnum: HTC_J15
There is no RUU for your device version that I'm aware of.