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[Tutorial] Why my IMEI missing & NO network?

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xsenman

Senior Member
Apr 9, 2012
3,914
2,367
Philippines
Your IMEI (International Mobile Equipment Identity) is transmitted to the Network provider the moment you switch ON your phone

It is used by your Network to identify the following

1) The first two numbers is RBI (Reporting Body Identifier) = who registered that type of phone ( verify here )

2) The next four numbers is TAC (Type Allocation Code) = what type of unit and its complete specifications

3)The next two numbers is FAC (Final Assembly Code) = who manufacture it

example :-

01 AEG
04 Samsung
07 Motorola
10 Nokia
30 Ericsson
41 Siemens
50 Bosch
51 Sony

4) The next six numbers is the Serial Number of the Phone

5) The last number is sort of a check sum, that verifies the previous numbers

Combined a total of 15 numbers is used by your network to get the complete information about your phone that is used against their database of Blacklisted phones and final approval to connect to their network, IF they were inaccurate or had complaints (like being stolen, not paid telecoms dues etc) it will be rejected and BLOCKED immediately from connecting to that Network

You can verify all this by entering you IMEI here and here

And also here to check if it is blacklisted

Your IMEI is also needed for networks to BLOCK your phone when needed as well as ANTI theft apps.

Hence if your IMEI changes or gets lost, it may fail to connect to the network, depending on the restrictions of that network provider.

It is clear that Flashing custom ROMS can cause your IMEI to Change or get deleted as they may be ported from another manufacturer or from another version of the same manufacturer as the IMEI embedded in the chip of your phone.

IF you want to AVOID this problem, safe you EFS folder the moment you think of Flashing any ROM that is NOT the original Firmware for that phone

It is noted that to resolve this problem you have to return to its original firmware to recover your embedded IMEI and do a progressive upgrade . eg. from GingerBread to ICS before going on to Jelly Bean

For ways to resolve IMEI problems visit EFS Problems and Solutions or My Android Solutions


Check this out!You , YES! you are an " Android ". Not your phone but U.

You Must watch this documentary concerning your privacy Terms & Conditions we had agreed to, by using a PC or Smartphone

How to say Thank you? *If you find any post helpful on XDA, please click on the Thanks button
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If you are using XDA App or Tapatalk, long press on the post and select :good: Thanks
Its easier to give "Feedback" in this manner than make an additional post.​

This post is linked to Pit Stop
 
Last edited:

xsenman

Senior Member
Apr 9, 2012
3,914
2,367
Philippines
You have the FAC 04 as Samsung which is correct but, HTC is also 04 :confused:

I believe this is also possible as some of the manufacturers are using more than one FAC (Final Assembly Code) and some do have the same FAC....end of the day only the manufacturer would have chosen what they wish to use, on the other hand the checksum of the 15 numbers in total, should give the correct model and specs to the network .
 

knuckles1978

Senior Member
Aug 6, 2012
1,329
440
It is noted that to resolve this problem you have to return to its original firmware to recover your embedded IMEI and do a progressive upgrade . eg. from GingerBread to ICS before going on to Jelly Bean

I had this very problem tonight. Flashed back to stock to try and fix a camera problem, then just installed cm10 to fix the partitions and applied my JB backup.

That's when I hit the imei problem. When I copied the efs folder across and rebooted it didn't fix it, came up some error. Then I manually copied the imei folder across, and then manually copy/replaced the loose files from my efs backup across into efs, leaving the extra files that were there from the install.

Meaning instead of completely replacing the efs folder with my backed up one, just adding all the files from the backup folder into the installed efs folder, replace any with identical names though.

Rebooted and it worked fine :) saving me having to go back to GB and progressively work my way back up. Nice..

Sent from my GT-I9000 using Tapatalk 2
 
Last edited:

knuckles1978

Senior Member
Aug 6, 2012
1,329
440
Sorry I'm new please try and bear with me..

Are you saying I should write it up nice and post it in there??

Sent from my GT-I9000 using Tapatalk 2
 

xsenman

Senior Member
Apr 9, 2012
3,914
2,367
Philippines
Sorry I'm new please try and bear with me..
Are you saying I should write it up nice and post it in there??

Nope...what you did has already been written and advised as a way, to resolve IMEI recovery by me in June 2012 and other methods were recently deleted by MODs as they can sort of edit the IMEI (which is illegal to do) :D..so, no problem, you have done it in one way ( because you had a backup) and there are other ways too...all compiled on that link as well as My Android Solutions, link below
 
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knuckles1978

Senior Member
Aug 6, 2012
1,329
440
Just had a proper read through that thread. Thanks :)
I thought that the way I did it was a little different because it didn't work when I tried replacing the installed efs folder with my backed up one, maybe not though.

Sent from my GT-I9000 using Tapatalk 2
 
Last edited:

skar_16

Member
Mar 10, 2012
47
4
nice info, I should try to look on those given threads about retrieving imei because I got one who's got unknown imei due to a noob upgrade without even backing up efs folder


Sent from my year one phone using Tapatalk
 

zaheerjk

New member
Jan 24, 2009
4
0
Your IMEI (International Mobile Equipment Identity) is transmitted to the Network provider the moment you switch ON your phone

It is used by your Network to identify the following

1) The first two numbers is RBI (Reporting Body Identifier) = who registered that type of phone ( verify here )

2) The next four numbers is TAC (Type Allocation Code) = what type of unit and its complete specifications

3)The next two numbers is FAC (Final Assembly Code) = who manufacture it

example :-

01 AEG
04 Samsung
07 Motorola
10 Nokia
30 Ericsson
41 Siemens
50 Bosch
51 Sony

4) The next six numbers is the Serial Number of the Phone

5) The last number is sort of a check sum, that verifies the previous numbers

Combined a total of 15 numbers is used by your network to get the complete information about your phone that is used against their database of Blacklisted phones and final approval to connect to their network, IF they were inaccurate or had complaints (like being stolen, not paid telecoms dues etc) it will be rejected and BLOCKED immediately from connecting to that Network

You can verify all this by entering you IMEI here and here

And also here to check if it is blacklisted

Your IMEI is also needed for networks to BLOCK your phone when needed as well as ANTI theft apps.

Hence if your IMEI changes or gets lost, it may fail to connect to the network, depending on the restrictions of that network provider.

It is clear that Flashing custom ROMS can cause your IMEI to Change or get deleted as they may be ported from another manufacturer or from another version of the same manufacturer as the IMEI embedded in the chip of your phone.

IF you want to AVOID this problem, safe you EFS folder the moment you think of Flashing any ROM that is NOT the original Firmware for that phone

It is noted that to resolve this problem you have to return to its original firmware to recover your embedded IMEI and do a progressive upgrade . eg. from GingerBread to ICS before going on to Jelly Bean

For ways to resolve IMEI problems visit EFS Problems and Solutions or My Android Solutions


This post is linked to Pit Stop

I have updated my Galaxy NOte N7000 with Some Custom ROMS , after that it changed my IMEI number ..

I cant use this mobile in INDIA i cant make and receive calls and TEXT but Internet data is working fine
. Please let know how can i change my IMEI number
I have Not taken any backup of EFS folder can i use other galaxy note files

Thanks
 

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    Your IMEI (International Mobile Equipment Identity) is transmitted to the Network provider the moment you switch ON your phone

    It is used by your Network to identify the following

    1) The first two numbers is RBI (Reporting Body Identifier) = who registered that type of phone ( verify here )

    2) The next four numbers is TAC (Type Allocation Code) = what type of unit and its complete specifications

    3)The next two numbers is FAC (Final Assembly Code) = who manufacture it

    example :-

    01 AEG
    04 Samsung
    07 Motorola
    10 Nokia
    30 Ericsson
    41 Siemens
    50 Bosch
    51 Sony

    4) The next six numbers is the Serial Number of the Phone

    5) The last number is sort of a check sum, that verifies the previous numbers

    Combined a total of 15 numbers is used by your network to get the complete information about your phone that is used against their database of Blacklisted phones and final approval to connect to their network, IF they were inaccurate or had complaints (like being stolen, not paid telecoms dues etc) it will be rejected and BLOCKED immediately from connecting to that Network

    You can verify all this by entering you IMEI here and here

    And also here to check if it is blacklisted

    Your IMEI is also needed for networks to BLOCK your phone when needed as well as ANTI theft apps.

    Hence if your IMEI changes or gets lost, it may fail to connect to the network, depending on the restrictions of that network provider.

    It is clear that Flashing custom ROMS can cause your IMEI to Change or get deleted as they may be ported from another manufacturer or from another version of the same manufacturer as the IMEI embedded in the chip of your phone.

    IF you want to AVOID this problem, safe you EFS folder the moment you think of Flashing any ROM that is NOT the original Firmware for that phone

    It is noted that to resolve this problem you have to return to its original firmware to recover your embedded IMEI and do a progressive upgrade . eg. from GingerBread to ICS before going on to Jelly Bean

    For ways to resolve IMEI problems visit EFS Problems and Solutions or My Android Solutions


    Check this out!You , YES! you are an " Android ". Not your phone but U.

    You Must watch this documentary concerning your privacy Terms & Conditions we had agreed to, by using a PC or Smartphone

    How to say Thank you? *If you find any post helpful on XDA, please click on the Thanks button
    thanks.jpg

    If you are using XDA App or Tapatalk, long press on the post and select :good: Thanks
    Its easier to give "Feedback" in this manner than make an additional post.​

    This post is linked to Pit Stop
    2
    I will add that information on their own IMEI number check here http://www.imei.info/
    2
    similarly, you can also recover your IMEI using this method: http://forum.xda-developers.com/showthread.php?t=1264021

    nice jobe OP! :)
    1
    I tested this site with my Nokia E71, and it's reporting my phone as Nokia 100 :eek:
    My Galaxy S3 appears as a Huawei U7510 on http://www.imei.info/, but http://imei-number.com/imei-number-lookup/ shows the correct information...
    1
    Sorry I'm new please try and bear with me..
    Are you saying I should write it up nice and post it in there??

    Nope...what you did has already been written and advised as a way, to resolve IMEI recovery by me in June 2012 and other methods were recently deleted by MODs as they can sort of edit the IMEI (which is illegal to do) :D..so, no problem, you have done it in one way ( because you had a backup) and there are other ways too...all compiled on that link as well as My Android Solutions, link below