Fix Galaxy Note4 N910C Bootloop & Invalid IMEI “Network” Problem

Many people who own a Galaxy Note 4 and have installed CyanogenMod 13 or another ROM based on Android 6.0 are experiencing a problem when they try to get back to stock Android 5.1.1. If you are suffering as well from the same problem than read further.

Have you installed CM13 or any other ROM based on Android 6.0 and now you wanna get back to stock on your Note 4 but suddenly the device experience a bootlooping problem? I come across this guide while I was looking to fix another Note 4 problem. I found this guide useful and decided to share with you. So if anyone is experiencing bootlooping issues with the Galaxy Note 4, follow the steps below carefully.

A XDA developer named as HmanA6399 made this guide for everyone who is suffering from bootloops on Note 4. He found the needed tools at the XDA community and created a step by step tutorial that you are going to find below;

Warning

Here at DoryLabs we shall not held any responsibility for bricked device, or any other problem. If you decide to make changes to you device do it at your own risk. You are doing it by your own so it’s only your responsibility if anything goes wrong.

How to fix Galaxy Note 4 Exynos N910C bootloop problem and Invalid IMEI Network

Phone Status: Custom ROM based on Android 6.0, root access, TWRP recovery, busybox installed, and smart install.

Requirements: a computer running Windows 7 or higher, Samsung USB drivers, adb drivers.

Test the adb drivers by running the command;

adb drivers

in the folder where the packages are installed.

How To Guide

First Step: Boot your phone into recovery and make a full backup. Find the backup under /TWRP/BACKUPS in internal storage. Copy the backup to your computer and to find it easily put on desktop and rename it to “backup 6.0” The backup is needed because it has the EFS folder inside, it isn’t compatible with ROMs and firmware lower than 6.o but it contains the IMEI number so keep this in mind.

Second Step: Your phone is supposed to be rooted and busybox installed. Enable USB debugging and grant root access to adb. If you are running CM13 it has a feature under Developer Options.

Now connect your phone to computer and open EFS professional. You should get a message box. Check “Always allow this computer” and click OK to continue.

Note: If you face any problem opening EFS-prof, try to restart it. Is still it’s not solved make sure you have allowed this computer in the message box that appeared on your phone, it is rooted and has busybox installed.

Once EFS loads, choose the third tab “Samsung tools”, navigate to “other tools” and choose format EFS folder.

If a msgbox appears saying “permission is denied”, it doesn’t matter. Click “Execute” again and it will show you “Can’t find mount points”. This means you are done.

Immediately reboot into recovery, never reboot into the system until you finish the third step. 

Third Step: Boot your phone in TWRP and wipe all expect the microSD and internal storage

After the wipe, turn of your phone. If it asks to install SuperSU, refuse it.

Boot into Download Mode and make sure it’s connected to PC.

Open ODIN and load the pit file of your phone. If you don’t have any then Google it. After that load the stock in AP tab. Check “Repartition” and then Start.

Congratulations, you did it!

But unfortunately the IMEI isn’t the one that your phone has so it means that you are not registered on a network. Really?! Yep, you fixed a problem but here it comes another one. Don’t panic! We gonna fix it too.

IMEI FIX

Requirements: Stock Android 5.1.1, the same computer you used before. backup you did in first step, a file explorer with root access on your phone, Ext4Unpacker tool for the computer.

1- Root and install TWRP

2- Backup using TWRP

3- Copy the backup to computer and rename “backup 5.1.1” and save in the same place with “backup 6.0”.

4- In the folder that contain the both backups make a new folder “EFS PORT“. Inside it make 2 other folders “BASE” and “PORT”

5- Using Ext4Unpacker tool extract “efs1.emmc.win” of the backup5.1.1  into the “BASE” folder.

6-  Extract “efs1.emmc.win” of the backup 6.0 into the “PORT” folder

You have now an EFS PORT folder containing two folders inside “BASE” and “PORT”. Each one of them has an EFS backup.

7- Delete “imei” folder of “BASE” and replace it with the one in “PORT”

8- Connect your phone to computer and copy the “BASE” folder and rename it to “efs”

Remember: Always small letters not CAPITAL.

9- In your phone install a file explorer with root access such as Root Explorer and grant it access to hte root. It will appear a msgbox to choose from.

10- Use Root Explorer to go to /efs folder of your phone’s root directory. It will refuse to delete the folder but the components will be deleted. Replace it with the new one you created on your computer..

11- Reboot the phone and you are done.

The phone might bootloop once or twice but do not worry. It’s fixed now and it’s alive again.