Help. HTC one M7 802w stuck on boot screen

Hi,
Device : HTC One Dual sim (802w/m7_cdug) middle east
my phone was unlocked, rooted, s-on, & with twerp recovery (stock rom),
i wanted to install an update from HTC available a few weeks back,
so i returned to stock recovery and tried to install the update (still unlocked).
after few minutes the phone restarted and is stuck on the HTC logo boot screen .

tried to flash ROM after re-locking the phone and , but unsuccessful.
i am able to flash recovery (twerp to stock and back) successfully.

Any help on this is appreciated .

getvar all given below :
nC:\Users\projects1\Desktop\PERSONAL\HTC>fastboot getvar all
(bootloader) version: 0.5
(bootloader) version-bootloader: 2.49.0000
(bootloader) version-baseband: N/A
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main: 7.17.402.15
(bootloader) version-misc: PVT SHIP S-ON
(bootloader) serialno: FA426W902021
(bootloader) imei: 351523061336539
(bootloader) meid: 00000000000000
(bootloader) product: m7cdug
(bootloader) platform: HBOOT-8064
(bootloader) modelid: PN0771000
(bootloader) cidnum: HTC__J15
(bootloader) battery-status: good
(bootloader) battery-voltage: 3978mV
(bootloader) partition-layout: Generic
(bootloader) security: on
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: dirty-d0e3b226
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0
all: Done!
finished. total time: 0.062s