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[Q] S3 GT-I9300 4.1.2 unlocker or downgrader

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klutchmeister
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(Last edited by klutchmeister; 8th January 2014 at 09:51 AM.) Reason: Updated question
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Unhappy [Q] S3 GT-I9300 4.1.2 unlocker or downgrader

I've searched far and wide but nothing actually helped. I hope someone here can shine some light please.

Hi, I am from the Philippines and I am a noob. My S3 GT-I9300 is a locked JB 4.1.2, and I need to unlock it because I want to install custom roms in it. Unfortunately I can't find anyway to unlock it. I read from somewhere that I should first downgrade to 4.1.1. Unfortunately still, I can't find anything that can help me downgrade to 4.1.1. I tried looking for downgrade tools and stock 4.1.1 firmwares to use with odin, but i've found nothing.

Please don't direct me to threads that makes me enter a code then main menu, umts, debug screen, etc. I tried it about 92.4 times. Doesn't work because it only works on 4.1.1, which is why I'm wanting to downgrade.

Help me, please? Thanks in advance.
 
boomboomer
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You refer to sim network lock? If your 4.1.2 rom was EMG4 or higher then there is no way to downgrade, efs partition format was changed to prevent user unlock.

If you have a backup of your efs, from before 4.1.2 was flashed, then you could restore the partition and unlock.

But you would then be stuck with 4.1 roms, before EMG4. Updating to a newer firmware will again network lock the phone.

Sent from my GT-I9300 using Tapatalk
Note: This quote doesn't automatically apply to everyone, decide for yourself if it might apply to you.

Quote:
Originally Posted by justruss View Post

What has this place become?

It's essentially a few people graciously answering the same repeating of immature, lazy, demanding questions from the masses.

Nobody searches. Nobody reads the first posts or titles of threads. Nobody even looks at posts a couple above their own.

 
klutchmeister
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Quote:
Originally Posted by boomboomer View Post
You refer to sim network lock? If your 4.1.2 rom was EMG4 or higher then there is no way to downgrade, efs partition format was changed to prevent user unlock.

If you have a backup of your efs, from before 4.1.2 was flashed, then you could restore the partition and unlock.

But you would then be stuck with 4.1 roms, before EMG4. Updating to a newer firmware will again network lock the phone.

Sent from my GT-I9300 using Tapatalk
Sorry, i'm a noob at this. What is EMG4 and how would I know what EMG my rom is?
So is there nothing I can do to network unlock my phone?
 
Tommienots
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Quote:
Originally Posted by boomboomer View Post
You refer to sim network lock? If your 4.1.2 rom was EMG4 or higher then there is no way to downgrade, efs partition format was changed to prevent user unlock.

If you have a backup of your efs, from before 4.1.2 was flashed, then you could restore the partition and unlock.

But you would then be stuck with 4.1 roms, before EMG4. Updating to a newer firmware will again network lock the phone.

Sent from my GT-I9300 using Tapatalk
Have the same problem here from Philippines also but the phone is bought at switzerland(swisscom/orange) network. But not quite sure about EMG4 rom version. My friend told me to work on his phone and he doesn't care if i root it or not. So heres my question, if i root it and change to custom rom will the sim lock be removed? Samsung has unlocked bootloaders and is easy to work with due to the system recovery unlike other phones.

Regards to the thread OP. Mabuhay!
Xperia M Dual [C2005]
 
boomboomer
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You both need to search, read and learn from the guides in general forum, stickies -as you're facing complicated issues and easily brick phone with limited knowledge.

Your baseband is shown in settings, about. If the phone had ever been updated to EMG4 then no, you'll need to purchase an unlocking code.

Rooting and custom rom does not remove sim lock.

Sent from my GT-I9300 using Tapatalk
Note: This quote doesn't automatically apply to everyone, decide for yourself if it might apply to you.

Quote:
Originally Posted by justruss View Post

What has this place become?

It's essentially a few people graciously answering the same repeating of immature, lazy, demanding questions from the masses.

Nobody searches. Nobody reads the first posts or titles of threads. Nobody even looks at posts a couple above their own.

 
klutchmeister
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#6  
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Thanks Meter 1
Posts: 8
Join Date: Sep 2013
Quote:
Originally Posted by boomboomer View Post
You both need to search, read and learn from the guides in general forum, stickies -as you're facing complicated issues and easily brick phone with limited knowledge.

Your baseband is shown in settings, about. If the phone had ever been updated to EMG4 then no, you'll need to purchase an unlocking code.

Rooting and custom rom does not remove sim lock.

Sent from my GT-I9300 using Tapatalk
Yep, I need to read a lot. I think I already bricked my phone twice, i just flashed stock roms but all i could find was jb 4.1.2.

My baseband is 19300DXEMB1, so is it EMB1? So it means i can downgrade?
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