[Desire 820 Q&A, Help & Troubleshooting] pet_bottle:
Hi

My phone is stuck at fastboot. Here is how it started:

It was working fine and suddenly it hanged and then turned off(Thought might be a battery issue as the battery is old and drops to 0 unexpectedly when under 30%). Later on, after plugging it into wall socket charger the orange LED kept blinking and on connecting it to the laptop it showed the device as Qualcomm HS-USB QDLoader 9008.

After trying a few things with power and volume button once I was able to turn it on to fastboot. Tried factory reset but it failed and went back to dead state.

Current situation:

I am able to turn it on to fastboot mode.

(How:By removing its battery for more than 40 sec's. Reconnecting the battery, then connecting it to laptop. Usually it turns on by itself and fails to load OS(normal boot) so goes dead and then turns on again after some time to fastboot by itself. You can try pressing the vol down and power button to turn it on )

Things I have tried:

1)Installing recoveries- all have failed including stock recoveries.

I have tried TWRP kitkat , lolipop ,CWM etc all the recoveries I could find for my device.

going to HBOOT->Recovery .Shows 3 android logo on skates and then restarts to fastboot mode by itself.

2)Flashing RUU/Stock ROM using the external SDCard method (renaming to 0PFJIMG and then HBOOT to autodetect and install) but in that all the things fail showing "FAIL-PU" and then later as that the package size is , probably because the HBOOT version in ROM is lower than my phones version.

I have tried installing/flashing this file : 0PFJIMG_A51_DTUL_M60_DESIRE_SENSE70_MR_hTC_Asia_India_3.17.720.3_Radio_01.01.010_U10305041_08.01.510 15_release_478672_combined_signed_2_4.zip (1.57 Gb)

Downloaded it from 3 different website , all fail to extract, says its currupt , dont know why!

To fix the HBOOT I have even tried the flash the lower version HBOOT using fastboot commands bt that also fails as the device is not able to load in the RUU mode:

fastboot oem rebootRUU -> this fails and the device turns off with orange LED blinking and the laptop not recognising the device any more(i.e as a usb/fastboot device, it shows it as an unrecognised device). Again I have to remove the battery and reconnect to make it On in fastboot mode again .

Due to this problem(command failure) , I am unable to temporarily flash lower HBOOT ( 0PFJIMG_A51_DTUL_3.17.720.3_signed_Hboot.zip)( Read it somewhere that flashing this will solve the problem of "device halted due to large image update" that comes when flashing with Sdcard) and then flash the RUU via fastboot as well.

Since I have S-On , I am not able to permanently downgrade the HBOOT version as well. + on top of that since recoveries are also not installing I am not able to install ROM using them.

fastboot erase cache -> also fails

Specs :

HTC Desire 820 Dual Sim

Relocked

A51_DTUL PVT SHIP S-0N

HBOOT-3.19.0.0000

OS-3.17.720.3

Radio- Sometimes shows "INVALID_VER_INFO" otherwise "01.01.010_U10305041_08.01.51015"

fastboot getvar all :

(bootloader) version: 0.5

(bootloader) version-bootloader: 3.19.0.0000

(bootloader) version-baseband: INVALID_VER_INFO

(bootloader) version-cpld: None

(bootloader) version-microp: None

(bootloader) version-main: 3.17.720.3

(bootloader) version-misc: PVT SHIP S-ON

(bootloader) serialno: removed

(bootloader) imei: removed

(bootloader) imei2: removed

(bootloader) meid: 00000000000000

(bootloader) product: a51_dtul

(bootloader) platform: hTCBmsm8939

(bootloader) modelid: 0PFJ10000

(bootloader) cidnum: HTC__038

(bootloader) battery-status: good

(bootloader) battery-voltage: 0mV

(bootloader) partition-layout: Generic

(bootloader) security: on

(bootloader) build-mode: SHIP

(bootloader) boot-mode: FASTBOOT

(bootloader) commitno-bootloader: 9cf29e72

(bootloader) hbootpreupdate: 11

(bootloader) gencheckpt: 0

(bootloader) mfg-name:

all: Done!

finished. total time: 0.031s

So in short , I am unable to flash recovery, go to oem reBootRUU mode to flash using laptop, flash RUU using ext micro SDcard and the device never turns on after a restart(Reboot fastboot option in fastboot mode fails)

Thanks in advance. Help will be appreciated.

I am not a noot but neither a pro. I welcome even complex solutions such as flashing eMMC etc.

[IMG="HTC 820 Dual sim sdcard RUU flash fail"]https://drive.google.com/open?id=1Z0aKfSad8qertiH9LACJcuE0ANu8z9nE[/IMG]