***WARNING*** PLEASE BACKUP your EFS!!

[dbrannon79]

***WARNING TO ALL***​

FLASHING ANY FIRMWARE CAN POTENTIALLY BRICK YOUR DEVICE ​

With that said, PLEASE use some precautionary measures to keep your device alive!​

There are many threads out there about making a backup copy of the "/efs" folder. that folder contains all of your IMEI information that is NOT replaceable! There are several cases all over the web, about people who have lost that information causing them not to have service, leaving them with "generic" IMEI's and some with all "0's"

I am posting this to help prevent thoes who are unaware of the consequences that happen when the EFS information is lost!

Here I will post a few guides and informational threads here in XDA to help with this.

EFS Tool for Windows

Guide for the Galaxy S II

A Story From the Vibrant

From the Galaxy Note​

I would also emphasize on making a nandroid backup of your complete system in recovery before starting to venture off onto any custom rom!
Here the folks at XDA have built a great community with a outstanding reputation to help one another advancing to the next level, also unlocking the extreme potential of our devices.

Be sure to "hit" the thanks button and when possible post a personal "Thanks" to the great devs and contributers we have here in XDA!

Feel free to add to this thread, any useful tips and such...


Thanks and God bless.

 

[dbrannon79]

I have not yet confirmed this, but here are three links to what may be a way for those who have lost their EFS to repair it!

there are other guides on how to recreate the efs folder but these tools may enable us to insert the correct information!

http://forum.gsmhosting.com/vbb/f611/android-language-editor-android-language-project-1543222/


http://xdaforums.com/showthread.php?t=1570342

Thanks to Pierreone, he has provided this link providing a individual from Poland that can repair your IMEI through TeamViewer for a small donation. This may be out only hope!!

http://forum.samdroid.net/f70/repair-imei-s2-5729/
Please if anyone tries these methods, report here to confirm success or failed!

Thanks.

 

[lorddavid]

I just copy and paste in my pc the EFS folder, thats enough? and how you can identify if there is a problem in the EFS?

 

[dbrannon79]

I just copy and paste in my pc the EFS folder, thats enough? and how you can identify if there is a problem in the EFS?

That should be enough, but I would make backups in at least to other ways just to be safe, it's better to be safe than sorry. a single file can get corrupt without your knowledge! find a on-line file host like Google drive and that way if your pc was ever to go down it will always be there. Just don't loose your password!!!

to know that there is a problem, check the about phone section in status, the device will show your phone info, look for the IMEI! if it reads all 0's or a generic number starting with "04" and ending like "40000" you have problems! that is a unique serial number that identifies your individual phone!

I'm also not sure that if you were to use it to call an emergency hot line like "911" they would be able to locate you in time! that may not be true tho!

 

[lorddavid]

That should be enough, but I would make backups in at least to other ways just to be safe, it's better to be safe than sorry. a single file can get corrupt without your knowledge! find a on-line file host like Google drive and that way if your pc was ever to go down it will always be there. Just don't loose your password!!!

to know that there is a problem, check the about phone section in status, the device will show your phone info, look for the IMEI! if it reads all 0's or a generic number starting with "04" and ending like "40000" you have problems! that is a unique serial number that identifies your individual phone!

I'm also not sure that if you were to use it to call an emergency hot line like "911" they would be able to locate you in time! that may not be true tho!

mines is ok, has al ot of different numbers. Just a question, what ab out the serial number? mines has only 00000000000

 

[dbrannon79]

mines is ok, has al ot of different numbers. Just a question, what ab out the serial number? mines has only 00000000000

the serial number so far is not a problem! it's the IMEI that you need to worry about! some refurbished phones and others that have flashed a custom rom will display an all "0's" serial no.

this is simply a helpful warning to make a backup before doing any modding! and finding ways for others to repair what is lost! if your phone is ok, just make a backup and your good!

One day we will figure out how to completely restore a lost efs and edit what is needed to get back to the norm!

 

[dbrannon79]

Thanks to Pierreone, I added a link to a thread that looks promising and has success reports!!

 

[roothorick]

Whew, I got lucky. I don't have an EFS backup and have flashed several custom ROMs, but I referenced About Phone against the label under the battery and my IMEI is still intact!

Could someone post what the Generic IMEI is so people can know whether their device is intact?

This is a a bigger problem than it sounds, because in some countries, changing the IMEI may be crime and land you jail time! If the IMEI under About Phone doesn't match the under-battery label, you could be in deep ****.

 

[braintweaker]

Could someone post what the Generic IMEI is so people can know whether their device is intact?

It is 004999010640000.
Have it, because the unlock made my network disconnect every 10 seconds.

 

[dmw0215]

About the efs folder ?

First of all Thank You for the heads up... I'm finding out a lot about backing up the efs folder but not a lot of detail about what exactly is contained in it other than imei and serial... probably because it shouldn't be fooled with but I like to know how things work in detail... is there any detailed post or site where I can get a complete explanation about it ? Complete file list/tree? What else does it control ? Can it be edited ?

 

[ninthsense]

EFS Tool for Windows

This utility works fine. Just wanted to mention 2 things that you need to set before running this successfully:

1. Settings -> developer options -> android debugging enabled
2. Settings ->Developer options-> Root access -> set to 'apps and adb'

 

[gtmaster303]

I followed the guide from the Galaxy S2 forum, and after the first command:
busybox cp -a /efs /sdcard/efs/

Every line says "can't preserve ownership of..." and "operation not permitted"
Am I doing this right?
I did get an efs folder on my internal storage which is about 5mb in size after that command anyway
The rest of the guide, all of the other commands went through ok.

 

[SillyB]

Holy crap, I wish I had listened to this warning! After flashing a great new rom and getting it 98% set up the way I like it I was deleting some junk apps the marketplace had auto installed, one of them (for wi-fi hotspots I think) was to blame and must have toasted my IMEI.

I thought, oh I'll just restore my CWM backup from an older setup - md5 error can't restore. DOH! After spending most of two days hunting for solutions (none of them linked in this thread worked, except I did get to where I could place calls with a generic IMEI but no data or text). I finally was able to recalculate the md5 manually and restore my old backup, which then got stuck at boot logo, then I flashed a new ROM and the IMEI still isn't back! After much reading I have come to understand NANDROID BACKUPS DO NOT TOUCH THE EFS. That is one thing that that I didn't understand, and the reason I thought I was safe. Please update the OP to state that so more people like me will listen to your advice.

Backup your EFS! Thanks for the warning

Sent from my SGH-I927 using xda app-developers app

 

[SillyB]

Victory!!!! :victory:

I was so close to just paying at http://sam.123unlock.nl/ and using their service to re-write my IMEI (because they show an unlock video using our phone and their software), but I kept digging in XDA and trying everything I could find. I tried the SIII IMEI editor, NV reader-writer, manually restoring the .nv_data.bin, mobiletech videos backup script...blah blah blah. I tried restoring CWM backups, flashing back to stock everything, using kies, I was trying everything! During all this I at times had no IMEI, all 000s, and a generic #, each of which provided different levels of services. I considered keeping the generic IMEI which AT&T didn't seem to mind but then I finally stumbled on a solution.

In reading the http://xdaforums.com/showthread.php?t=859914 post which is linked to in the "A Story From the Vibrant" in the OP I tried the abd EFS tar command and executed it on another Captivate Glide I have that had some water damage but is mostly still functional thinking I could overwrite the entire good EFS of that phone to my good phone with the hosed IMEI. I used AROMA http://xdaforums.com/showthread.php?t=1646108 and deleted the EFS from CWM (I felt like adb and terminal weren't effective since the OS was still awake) and then restored from my working EFS tar, then wrote on top of that the first backup of the hosed EFS I had from before I started messing with it (thinking I'd try that before trying just the other phone's E)FS.

When I rebooted I had the correct serial and IMEI back for the phone! It is now working 100%

 

[greeneyez15o]

I flash alot from to rom, if i use the aroma file manager n save the entire efs folder on my external drive ,if i were to ever run into problems can i go bak to aroma file manager n just restore the efs folder and make everythinfunction again ?

 

[SillyB]

Some guys say yes, others say use the tar command to preserve file permissions. I backed it up both ways. When I used aroma I deleted the files and replaced them rather than over-writing the corrupted ones and it worked fine for me.

Sent from my SGH-I927 using xda app-developers app

 

[Timelord83]

So I just got my captivate glide bought it used and I followed thegreatones instructions to get CM 10.1 using the factory image to get it to 4.X then flashing the rom.. and after i flashed CM 10.1 my imei was gone. SIGH. I don't have a backup, which of the paid services works the best? who has tried them?

 

[jzamoras]

I managed to make EFS Pro work but the glide is not listed and I don't see any partition to backup. Am I missing something?

 

[Aquethys]

So I just got my captivate glide bought it used and I followed thegreatones instructions to get CM 10.1 using the factory image to get it to 4.X then flashing the rom.. and after i flashed CM 10.1 my imei was gone. SIGH. I don't have a backup, which of the paid services works the best? who has tried them?

I haven't tried any but I would first give AT&T a call. They can probably assist you. And I believe there's a 14 day return date, I believe AT&T only checks the physical aspects of the phone.

I managed to make EFS Pro work but the glide is not listed and I don't see any partition to backup. Am I missing something?

It worked for others. Check to make sure you have all Glide drivers installed and reread the OP please Thanks!

 

[jzamoras]

Finally I used an older EFS Tool and it worked!