• Root access ► TowelRoot ► For GNG8 or higher firmwares, read this thread.
• Mobile Odin Pro ► Play Store.
• A bit of patience.
• Before you begin, read the guide carefully at least a couple of times.
• Backup your EFS folder using one of this tools: EFS Pro (PC), Samsung Tool (Mobile) or AntaresOne's tool (Mobile).
• I suggest to make a backup of everything you need by using Titanium Backup.
1) Download from Google Drive the zip file of the ROM and copy it to the internal/external memory.
2) Download and install Mobile Odin Pro.
3) Grant root access.
4) Press on OTA/Update ZIP and choose the zip to flash.
5) Put the tick on: Enable EverRoot, Inject Superuser (SuperSu) and Inject Mobile Odin.
6) Make sure you have at least 50% charge.
7) Press on "Flash firmware" to start the flash.
8) Flash via Odin the Modem/NON-HLOS matched to the ROM. For a guide on how to do it, read the note number 4.
NOTE 1: Whenever you flash any zip file, always remember to put the tick on Enable EverRoot, Inject Superuser (SuperSu) and Inject Mobile Odin otherwise you will lose root access.
NOTE 2: If the zip is a Custom ROM, you have always to remember to put a tick on all the options listed in step 5.
NOTE 3: If the zip is a MOD, flash it as if it were a ROM. You don't need to flash Modem, NON-HLOS or Kernel. Just put the tick only on: Enable EverRoot, Inject Superuser (SuperSu) and Inject Mobile Odin.
1) Download drivers from HERE (skip this step if you have already installed them).
2) Download Odin 3.07 or Odin 3.09.
3) Reboot your device into download mode.
4) Click on PHONE (Odin 3.07) or CP (Odin 3.09) and choose the Modem.bin/NON-HLOS.bin that you have to flash.
5) Put the tick only on "F. Reset Time" and press "Start".
6) Once it finished, press and hold Power button for 10 second and then get back immediately into download mode.
7) Repeat twice and then go to Settings > About > Baseband version and check that your Modem has changed.
NOTE 5: This procedure is compatible with all the TouchWiz based Custom ROMs, not with AOSP, AOKP, MIUI or other ROMs.
@Chainfire for Mobile Odin.
@Wuby986 and @slim80, my dear friends, for giving me help in many situations.
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