This tutorial will help you fix HTC Desire 820n phones that are stuck in boot loop or has a corrupted software. This tutorial is only for the European variant with CID J15.
How to find the CID of your phone?
To find the CID of your phone, turn off your phone and then press and hold volume down and power button together. Your phone will enter bootloader mode. You will find the CID there like CID-HTC_ _J15 . If your CID number is different from this , this tutorial will not work for you. Also find the OS Version. This tutorial is for OS verison 3.17.401.3 or below. If your OS version is greater than this , then this procedure will fail. Also your OS version should have 401 in it like x.x.401.x .
PLEASE NOTE: Some HTC Desire 820 models have a common emcc problem and it might mimic software issue. If your phones problem is caused by corrupted emcc, then this tutorial will not help you. Also note that flashing a phone has its own risks. Your phone may even go dead. If you have not flashed a phone before and you do not understand the basic procedure, do not follow this tutorial. This tutorial is only meant for people with some technical knowledge. Also keep in mind that you will lose all data on your phone. I will not be responsible for any damage caused to your phone by following this tutorial.
- Download the firmware/flash file from here
- Rename the flash file from 0PFJIMG_A51_UL_M60_DESIRE_SENSE70_MR_HTC_Europe_3.17.401.3_Radio_01.01.010_U10305041_08.01.50512_release_476105_signed_2_4.zip to 0PFJIMG.zip (If you do not see the .zip extension in the main file you downloaded then just rename the file to 0PFJIMG)
- Copy the renamed file to the root (not inside any folder) of your SD card. Make sure you use a good SD card.
- Turn off your phone and insert the SD card into your phone. If your phone is in reboot loop and you cannot turn off your phone, press and hold volume down button as the phone goes off and turns back on. Your phone will enter boot-loader mode. In boot-loader mode you will find option to turn off your phone.
- Now turn the phone back on by holding the volume down and power button together, you phone will enter boot-loader mode again. Now your phone will check for the flash file present in your SD card. After a short while it will ask you whether you want to flash the file, select yes. Now wait for the process to complete. Make sure your phone has at-least 50% charge or just plugin in the charger while this process takes place. You phone should not go off while this is happening. This process might take up-to 40 minutes so please have patience and let the process complete.
- Once the process is complete reboot your phone. You will now see the initial setup screen. Complete the initial setup to start using your phone.