I faced this problem since last 6 month that my phone was keep saying its not registered in the network and Insert SIM and continuously my network signals was going on and off.
So what i tried so far,
1. I did my phone factory reset nothings seems to be worked.
2. Manualy choose the mobile network from Settings -> More.. ->Mobile networks ->Access point Names ->Then chose my APns as my service provides Nothings worked
3. Then I reset the APN as defult by doing Settings -> More.. ->Mobile networks ->Access point Names ->Menu Button->Reset to default Not worked
When I pressed *#06# It didn't gave me any result the following code is for getting the IMEI no for my mobile.
Then I thought there is a serious problem with my IMEI number.and this directly linked with my efs folder which was corrupted.
What is an “EFS”?
EFS refer to a folder location called /EFS in Samsung’s Android devices. It is a very sensitive folder hidden within the deepest core of your smartphone’s internal file system and is very essential to the functions of our smartphones.One of the very sensitive information you can find in this folder is the information regarding your phone’s unique IMEI number. As you may have guessed by now, it also contains other unique identifying
numbers for your smartphone including the MAC address for your smartphone’s radios, as well as the MEID, ESN, as wells as the registered phone number for locked smartphones
The Danger to EFS
Normally, the EFS folder is highly protected. Rooting and flashing ROMs normally do not touch this part of the device. Unfortunately, there is no such thing as a controlled environment where everything goes according to plan in the real world. Sometimes, a process hits the EFS folder, or ends up corrupting the data within.
The EFS is also likely to be corrupted by users who like to unlock smartphones since it usually involves editing the data within the EFS folder. Once the data is corrupted, the only way to get it back to working order is to restore the data as is.
The loss of the EFS folder may cause your phone to no longer be recognized by your carrier or some of your radios may no longer work. This breaks the device as a whole no matter how many times you reinstall a ROM.
Even if you are not planning to modify the EFS folder itself, you can still accidentally corrupt that data. That is why even if the process of rooting and flashing ROMs does not require you to do so, it would be prudent to back up the folder. This would be a classic case of being “better safe than sorry”.
Why Modify the EFS
Messing with the EFS is what you would call some “high level stuff”. People normally don’t mess with this folder due to the high risk of making the smartphone unusable. The most common use of editing the EFS folder is to unlock the smartphone so it can be used on other carriers.
This is all about the theory about the EFS folder but you should carefully read it it help to understand the usability and importance of that folder.
What is BusyBox in android??
BusyBox is a collection of powerful command-line tools. After rooting android device we need to install busybox binary to run some applications which require root privileges and use BusyBox from the command-line.
So Coming to the point 4 easy step to Fix this Above Issue
Insert SIM card to access network services fix not register on network
There are two different approaches for two different one for rooted phone and other for normal phone
What is rooted in Android Phone:
As Android derives from the Linux kernel, rooting an Android devicegives similar access administrative permissions as on Linux or any other Unix-like operating system such as FreeBSD or OS X. Root access is sometimes compared to jailbreaking devices running the Apple iOS operating system.
So in Simple terms its superuser its like admin access you allowing the user for any workaround on the device by bypassing the os restrictions.
NOTE:This solution required your phone to be rooted
How to check if your phone is rooted or not if you are not sure about your phone??
Use this app
Rootchecker
https://play.google.com/store/apps/details?id=com.helroz.GSII_Repair&hl=en
Solution for rooted android phones:
This is a very simple solution
GSII_Repair
Step 1-https://play.google.com/store/apps/details?id=com.helroz.GSII_Repair&hl=en
go to/press Repair GSII tab or screen then follow upto step 3
If any chance its giving an error like BusyBox error so you need to download the
BusyBox
https://play.google.com/store/apps/details?id=stericson.busybox&hl=en
After that try it again the Step-1 your phone should work like a champ as usual normal with every network stick up.
By pressing the *#06# you should be able to get your IMEI
Solution for Normal phone /not rooted phones:
As in the above point this solution need your phone to be rooted
So there is a easy way to rooted your phone without connecting to you computer with the help of an android App.
Step -1 framaroot
Root your phone By using this App
http://framaroot.net/
Step -2 BusyBox
https://play.google.com/store/apps/details?id=stericson.busybox&hl=en
Step -3 GSII_Repair
https://play.google.com/store/apps/details?id=com.helroz.GSII_Repair&hl=en
go to/press Repair GSII tab or screen then follow upto step 3
So your should be now ready to access network.By pressing the *#06# you should be able to get your IMEI ok then you saved your phone from getting bricked cheers.
Disclaimer:
ROOTING YOUR PHONE WILL PROBABLY VOID YOUR WARRANTY FROM BOTH THE CARRIER AND THE MANUFACTURER.DO THE ABOVE ACTIONS AT YOUR OWN RISK.IF YOUR PHONE GET BRICKED PLEASE DON'T CONTACT ME
