IMEI Recovery
IMPORTANT
FOR THIS PROCESS TO WORK YOU MUST HAVE A GOOD COPY OF YOUR /efs DIRECTORY TAKEN PRIOR TO THE PROBLEM HAPPENING. IF YOU DO NOT HAVE THIS YOU WILL NOT BE ABLE TO RECOVER.
DISCLAIMER - THIS IS AN AMALGAMATION OF IDEAS, PROCESSES AND GUIDES FOUND ONLINE ALONG WITH MY OWN MODIFICATIONS AND PROCESSES THAT I HAD TO MAKE TO GET THE PROCESS TO WORK FOR ME.
ALTHOUGH I HAVE PERFORMED THIS PROCESS IN FULL AND IT HAS WORKED FOR ME I AM NOT RESPONSIBLE FOR ANY DAMAGE OR DATA LOSS THAT ARISES FROM FOLLOWING THIS GUIDE. BY USING THIS GUIDE YOU ARE ACCEPTING ANY AND ALL RESPONSIBILITY FOR ALL ACTIONS AND THEIR RESULTS.
IT GOES WITHOUT SAYING THAT PERFORMING THIS PROCESS WILL INVALIDATE YOUR WARRANTY BUT IF YOU ARE ALREADY ROOTED AND RUNNING CUSTOM SOFTWARE THEN YOU HAVE ALREADY INVALIDATED YOUR WARRANTY ANYWAY.
This is a common problem that usually occurs when a problem is encountered flashing a file from Recovery. Please take the precautions listed below, it will save you a lot of trouble should you ever suffer from this problem.
Backup Process
There are 3 ways that I use to back up the /efs directory.
These are:
1 - Manually copy /efs to your SD Card and make another copy somewhere safe (Computer, Dropbox, etc).
2 - Use HC-kTool to make a backup image of your /efs directory.
3 - Use Galaxy S Unlock AND GSII Repair to make backups of your original /efs directory (These are both the same but by doing both you have two copies of /efs available should you need it).
All Apps available from the Google Play Store or can be downloaded in the AppPack from here
At the end of this process you will have 4 copies of your /efs directory on your SD Card as well as any dulicates you created externally in step 1. This might seem like overkill but trust me taking 5 minutes creating these will save you hours and possibly quite a bit of money in repair costs in the long run should you ever need to recover!
Now you have your backups lets hope that you never need them, but should you then...
Recovery Process
Acknowledgements
Based on original post by XDA Member
vaskodogamagmail with more detail and modifications to make process work added by me.
Original Post
Symptoms
You may have one, some or all of the following:
No Signal
Emergency Call Only
No Network
IMEI 004999010640000
IMEI 000000000000000
IMEI
(To check your IMEI number either enter *#06# dial into the dialer or check in Settings, Phone Information)
Prerequisites
Rooted Phone
Try the following processes in order until the problem is resolved.
Method 1:
Open HC-kTool and choose "Restore efs from backup (DANGEROUS!)" then choose "Restore IMG". Once completed you will be prompted to reboot. Perform Reboot and if all has gone well you will have a working phone again.
Method 2:
Open Galaxy S Unlock app and select "Restore saved EFS Folder". This will come up with a response saying "Done". Reboot and see if your phone is working again.
Method 3:
Open GSII_Repair and perform Options 2 and 3. Your phone will reboot. Once it has rebooted see if your phone is working.
Method 4:
Open GSII_Repair and select "Restore saved EFS Folder". This will come up with a response saying "Done". Reboot and see if your phone is working again.
Method 5:
This is the last chance (and the one that after tweaking to what you see below worked for me).
You will Need the following:
Stock GB ROM
Insecure Kernel
ODIN
Quick Root
All of these can be downloaded in the IMEIFix.zip which can be downloaded from
here.
Android SDK and ADB instaled on your Computer or a Terminal App on your Phone (Personally I prefer ADB from Computer but you choose whichever you are most comfortable with).
We are going to restore your phone to as close to original stock a possible. No data wil be removed from your SD Card(s) but all installed apps, customisations, ROMs and Kernels will be removed. Please backup everyting you need before runnng this process.
If you are able to make a Nandroid Backup of your Rom you will be able to recover this at the end of the process.
Open ODIN
In Options select "Auto Reboot" and "F. Reset Time".
Select the following files from the "OriginalRom" folder on your computer:
Bootloader -> KERNEL_I9100XEKDB_CL161513_REV02_user_low_ship.tar.md5
PDA -> CODE_I9100XEKDB_CL161513_REV02_user_low_ship.tar.md5
Phone -> MODEM_I9100XXKDH_REV_02_CL995882.tar.md5
Reboot your phone into Download Mode (Hold down Home, Volume Down and Power when turnng on).
When in Download Mode connect to Computer via USB.
You will get a Ready message in one of the top boxes in ODIN. When you have this press the Start button.
After a while your phone will reboot and load up into it's Stock setup.
Configure the settings and then Power down the Phone.
Once Powered down go into Download Mode again (same process as above).
In ODIN press Reset.
Set the same options as before.
This time only set the Bootloader box. Select the file from the "InsecureKernel" folder on your computer - NOTE Insecure means that it is able to be rooted, not that there is a security issue with using it. We will be replacing this later anyway.
Check you have the Ready in the top box in ODIN and press Start.
Once finished your phone will reboot to stock again. IMPORTANT - Disconnect the USB cable before proceeding.
Go to Settings, Applications, Developer Options.
Turn ON "USB Debugging".
Connect USB cable to Computer and Phone.
Open "Samsung Quick Root"
Select "Reboot Device When Finished"
Press "Root Device"
Some text will scroll on the screen and then phone will reboot.
This will have installed SuperUser, Busybox and Rooted your phone.
Install a Root capable Explorer app, I used Es File Explorer, either download from the Play Store or you can install if from the Apps folder of IMEIFix downloaded above.
Open a Command Prompt on your Computer
Enter the following commands:
adb shell
su
busybox umount -l /efs
exit
exit
Using your chosen exporer delete the efs folder from the root of your phone.
Reset the phone, after that open your explorer again and browse to the Root, the efs folder should have recreated and will contain files. These are new and are system generated.
Go to the efs folder using your chosen explorer, and delete "nv_data.bin" and "nv_data.bin.md5".
Go to the working back up of your efs folder on your SD Card, copy the "imei" folder to the efs folder at the root of your phone, then again go to the backed up efs folder on your SD Card and copy the "nv_data.bin" file to your efs folder at the root of your phone using your explorer. Once you have copied this file, please rename the new file to "nv_data.bin.bak".
Make another copy of the "nv_data.bin" file in the backed up efs folder on your SD Card and paste this into the efs folder at the root of your phone again.
On your Computer open a command prompt and enter the following commands:
adb shell
su
chown 1001:radio /efs/nv_data.bin
Reset your phone.
You should now have your Original IMEI, check this by dialing *#06# call into the dialer. If you have the correct IMEI then you are done. You can either reinstall your usual ROM, Apps, Kernel etc manually or restore an existing backup.
If you need to install a Recovery with CWM (to restore backups or install new ROMs and Kernels then please follow these steps:
Install Mobile Odin from ChainFire from the Play Store (or if you are an XDA user you can download from here)
If you have used the XDA version you will also need the eu.chainfire.mobileodin.flashkernel.i9100.v2-1 apk file, this is in the IMEIFix download above in the Apps folder.
Copy the Kernel-V7.tar file from the CWMKernel folder in IMEIFix to your SD Card.
Open Mobile Odin and from there open the Kernel-V7.tar file. This will flash Dorimanx 7.45. If you now boot into recovery you can flash what you need to in the usual way.
By following the process above you will likely find that the Triangle Alert is now on your screen when booting yor phone indicating that your bootloader has been modified. Although this makes no functional difference to your phone you can remove this alert by installing TriangleAway from the Play Store (or if you are an XDA user you can download from here. This will reset the flash counters in your phone and remove the warning.
If you still have the wrong or no IMEI then you will need to seek further help.
There is no obligation but if this guide has just saved your phone and you feel you would like to show your appreciation there is a "Donate" button on the left, please feel free to use it.