LG H850 failed to flash, and stuck in boot loop

[xpboy]

Hi,
I need help plz, i have a LG H850 failed to flash, and stuck in boot loop with Your device is corrupted, It cannot be trusted and will not boot.
i cant unlock the bootloader because its not supported in my device, also i cant go to download mode. i always receive this message.
any idea ?!!

[Octopus box]

Hello.

Please post here full Software logs of all operations, which You've performed with the phone.

[xpboy]

Originally Posted by Octopus box

Hello.

Please post here full Software logs of all operations, which You've performed with the phone.

The phone was on nougat 7.0 , i tried to write the only firmware i found in octopus support area, after writing modem, system , boot, ..etc .. failed on writing param.img ( not sure about the name) and since then the phone stuck on boot loop, not charging, no download mode, locked bootloader (NOT supported for unlock) , the phone is H850

[Octopus box]

Please post here full Software log of "Write Firmware" operation. Log files are saved in "C:\Program Files (x86)\Octoplus\Octoplus_LG\LOG" folder.

[xpboy]

Originally Posted by Octopus box

Please post here full Software log of "Write Firmware" operation. Log files are saved in "C:\Program Files (x86)\Octoplus\Octoplus_LG\LOG" folder.

06/06/2017 21:06:48 > Checking data...06/06/2017 21:06:49 > OK
06/06/2017 21:06:49 > Platform: LG Qualcomm
06/06/2017 21:06:49 > Selected port: COM54
06/06/2017 21:06:49 > Selected model: H850
06/06/2017 21:06:49 > Reading info...
06/06/2017 21:06:50 > Model ID: LG-H850
06/06/2017 21:06:50 > IMEI: 357657-07-431042-2
06/06/2017 21:06:50 > Android version: 7.0
06/06/2017 21:06:50 > Battery level: 24%
06/06/2017 21:06:50 > SW Version: 06/06/2017 21:06:50 > H85020c
06/06/2017 21:06:59 > Mode: Normal
06/06/2017 21:06:59 > Writing phone firmware without real necessity is at your own risk.

Downgrade may lead to phone damage!

Please, make sure the phone's battery is fully charged.
Disconnect all other devices from the computer (including phones, modems, etc.) and close all other running programs.
To avoid errors in the flashing process, use a clean PC (without any installed drivers for other Qualcomm-based devices).
You should not run any other programs or attach new devices to your computer during the flashing!
06/06/2017 21:07:02 > Opening "H850_V10c_00_OPEN_EU_OP_0415.oct"...06/06/2017 21:07:02 > OK
06/06/2017 21:07:02 > Switching to Download mode...06/06/2017 21:07:27 > OK
06/06/2017 21:07:27 > Initializing flash...06/06/2017 21:07:30 > OK
06/06/2017 21:07:30 > Setting options...06/06/2017 21:07:32 > OK
06/06/2017 21:07:32 > Reading partitions...06/06/2017 21:07:57 > OK
06/06/2017 21:07:57 > Formating USERDATA...06/06/2017 21:08:10 > OK
06/06/2017 21:08:10 > Formating ENCRYPT...06/06/2017 21:08:14 > OK
06/06/2017 21:08:14 > Writing PrimaryGPT...
06/06/2017 21:08:14 > LAF Error: 80000121.
06/06/2017 21:08:14 > Trying second method...06/06/2017 21:08:14 > OK
06/06/2017 21:08:14 > Writing laf...06/06/2017 21:08:18 > OK
06/06/2017 21:08:18 > Writing factory...06/06/2017 21:08:18 > OK
06/06/2017 21:08:18 > Writing persist...06/06/2017 21:08:19 > OK
06/06/2017 21:08:19 > Writing system...06/06/2017 21:17:30 > OK
06/06/2017 21:17:30 > Writing cust...06/06/2017 21:17:33 > OK
06/06/2017 21:17:33 > Writing BackupGPT...06/06/2017 21:17:33 > OK
06/06/2017 21:17:33 > Writing PrimaryGPT...06/06/2017 21:17:33 > Failed!
06/06/2017 21:17:33 > Performed by 2.6.7 Software version.
06/06/2017 21:17:53 > Connecting to server support.octoplusbox.com:82...06/06/2017 21:17:53 > OK
06/06/2017 21:17:53 > Authorizing...06/06/2017 21:17:54 > OK

[Octopus box]

According to your Software log, You have downgraded phone's firmware version from V20c to V10c. Downgrade may lead to phone damage!:

Writing phone firmware without real necessity is at your own risk.

Downgrade may lead to phone damage!

If the phone doesn't go into Download Mode, currently we have no solution on how to repair boot loaders in this device.