Unbrick Lumia 520 in Black Screen Mode – No hardware

Mirosoft provided Windows 10 Technical Preview for almost all Lumia devices that are running Windows Phone 8.1. After the launch of Windows 10 Technical Preview for most of Lumia devices, which is the second launch of Windows 10 Mobile Technical Preview, Some of the Lumia devices bricked while downgrading from Windows 10 to Windows Phone 8.1 which includes low end devices like Lumia 520/620, Lumia 525. As Lumia 520 is mostly used device among low end phones, Most of Lumia 520 users faced this issue.


Many Lumia phones bricked during downgrading of Windows Phone 8.1 from Windows 10 TP with WPRT ( Windows Phone Recovery Tool ). Microsoft later fixed this issue by updating WPRT tool. But this tool has not worked for completely dead and bricked Lumia devices. To unbrick Lumia 520 which is completely dead and unresponsive, here is the process. To unbrick Lumia 520, which is not responding an not vibrating on pressing Power + Volume -, follow this steps carefully.

Unbrick Lumia 520 in Black Screen Mode – Completely dead :

1) First download Windows Phone Recovery Tool and install it on your PC.

2) Download the missing Drivers from the below link provided. These drivers will install while installing WPRT. Ignore this step, if already installed.

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Download drivers here.


3) While downgrading with WPRT, a .ffu file is downloaded from internet which is the required phone installer. Generally the location will be ” C:\ProgramData\Microsoft\Packages\Products\rm-914 ” if your O.S is installed in C drive. The file size is more than 1 GB.

4) Now create a new folder “dump” in C drive.

5) Now download Hex file for Lumia 520 from the below link. ( change below file extension to .hex after downloading ). Place the Hex file in dump folder. Now navigate to WPRT installed folder which is “C:\Program Files (x86)\Microsoft Care Suite\Windows Phone Recovery Tool”. Scroll down and find thor2.exe file. This file will create 2 GPT file in the dump folder.

[sociallocker id=53]

Download hex file here.


unbrick lumia 520

6) Now open Command Prompt as administrator and navigate to above path and execute the following command.

thor2 -mode ffureader –ffufile "C:\ProgramData\Microsoft\Packages\Products\rm914\RM914_3058.50000.1425.0007.ffu" -dump_gpt -filedir C:\dump\

replace italic path with your downloaded file name. Find it inside. " C:\ProgramData\Microsoft\Packages\Products\rm914"

7) Now the above code creates 2 GPT files in dump folder.

lumia 520_1

8) Now connect your dead Lumia 520 phone to PC. Now we are going to flash Lumia 520 bootloader. Execute the below command in Command Prompt.

thor2 –mode emergency –hexfile C:\dump\HEX.hex –mbnfile C:\dump\GPT0.bin – orig_gpt

9) Wait for the process to complete. Now boot your Lumia 520 device. Hold Volume Down and Power button at the same time. Your device will boot and stuck at Red Screen.

unbrick lumia 520

10) Don’t worry. We have not installed the software yet. Open command prompt and type the below command.

thor2 -mode uefiflash -ffufile "C:\ProgramData\Microsoft\Packages\Products\rm914\RM914.ffu" 

replace RM914.ffu with your downloaded .ffu file name.

11) Now the flash begins and completes the process. If the process fails, reinsert the battery and try above step again.

unbrick lumia 520

12) Now your phone boots and green screen appears. Now execute this command in the same command prompt.

unbrick lumia 520

thor2 -mode rnd – bootnormalmode

13) You will get a status “Device is already in the normal mode. (NCSd running) ” and exited with success. Your device will boot normally now.

unbrick lumia 520

That’s it. Now you have unbrick Lumia 520 in Black Screen Mode. If your phone strucked in Red Screen Mode, proceed from Step 11.

About the author

Anil Reddy Tirugudu