[Q] Unlocking an AT&T SGS3 on 4.3 (Already rooted)

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rikonor

New member
Dec 28, 2013
3
0
Hi!

I'm sorry if this has been asked before but I just can't find a definitive answer to this and I've been trying to search for an answer for nearly a week now.

My boss received a used Samsung Galaxy S3 from a friend of his in the states. It is a locked AT&T phone (SGH-I747) and it is on 4.3.
I managed to root the phone using CF-Auto-Root, which disabled Knox (whatever that is) and also installed CWM and was planning to flash 4.1.1 so I can unlock the phone using the *#NUM# method.

After reading a bit I've seen many people saying that you can't "downgrade" from 4.3 to anything else because it will brick your phone. Hence, I did not try and flash any other rom on the phone.

So I guess I'm just trying to get a definitive answer here because I can't find anything but rumors on this subject. I mean it's weird, I'd expect if you couldn't downgrade from 4.3 than it would be a bit more documented.

Has anybody tackled this problem with success?
Thank you
 

audit13

Inactive Recognized Contributor
Jun 4, 2012
12,911
5,052
Toronto
The normal method for the end user to conduct software updates and upgrades is via OTA or Kies. Using Kies or OTA doesn't require the end user to know about download mode, fastboot, or recovery mode. Samsung probably did not want non-technical users to brick their phones using download mode and Odin. It would be too easy for a non-techie to use the wrong firmware, tick the wrong options in Odin, etc.

I'm sure the fact that you cannot downgrade the bootloader has been well document by Samsung and its service centres. Based on the contents of my first paragraph, there would be no need for Samsung to advertise to the end user that the bootloader cannot be downgraded.
 

htc_softbank

Senior Member
Oct 17, 2010
146
11
Hi!

I'm sorry if this has been asked before but I just can't find a definitive answer to this and I've been trying to search for an answer for nearly a week now.

My boss received a used Samsung Galaxy S3 from a friend of his in the states. It is a locked AT&T phone (SGH-I747) and it is on 4.3.
I managed to root the phone using CF-Auto-Root, which disabled Knox (whatever that is) and also installed CWM and was planning to flash 4.1.1 so I can unlock the phone using the *#NUM# method.

After reading a bit I've seen many people saying that you can't "downgrade" from 4.3 to anything else because it will brick your phone. Hence, I did not try and flash any other rom on the phone.

So I guess I'm just trying to get a definitive answer here because I can't find anything but rumors on this subject. I mean it's weird, I'd expect if you couldn't downgrade from 4.3 than it would be a bit more documented.

Has anybody tackled this problem with success?
Thank you

Right now there is no free way to unlock your phone if it's on 4.3.(you can downgrade to older stock android, but the 4.3 bootloader remains and messes up your phones IMEI until you go back to stock 4.3)

Anyhow, the reason you can't downgrade the bootloader is because there is no method discovered to do this yet. I ended up using gsmliberty to unlock, and they have a deal that you get a free unlock if you take a video when you unlock and upload it to vimeo/youtube using the format they request.

I did that and they re-funded me very quickly. So IMO this is the best "free" method until we can downgrade from 4.3 bootloader and do the 4.1.1 free unlock.

I was in the same situation, and I had to pay for an unlock code.

If you want to see me unlock it, here is the video: http://vimeo.com/96549806
 

Larry2999

Senior Member
Feb 7, 2014
363
78
Atlanta, GA
Hi!

I'm sorry if this has been asked before but I just can't find a definitive answer to this and I've been trying to search for an answer for nearly a week now.

My boss received a used Samsung Galaxy S3 from a friend of his in the states. It is a locked AT&T phone (SGH-I747) and it is on 4.3.
I managed to root the phone using CF-Auto-Root, which disabled Knox (whatever that is) and also installed CWM and was planning to flash 4.1.1 so I can unlock the phone using the *#NUM# method.

After reading a bit I've seen many people saying that you can't "downgrade" from 4.3 to anything else because it will brick your phone. Hence, I did not try and flash any other rom on the phone.

So I guess I'm just trying to get a definitive answer here because I can't find anything but rumors on this subject. I mean it's weird, I'd expect if you couldn't downgrade from 4.3 than it would be a bit more documented.

Has anybody tackled this problem with success?
Thank you

What everyone else has said here is correct. You can't safely downgrade from 4.3 to free unlock - or free unlock by any other means for that matter once you are on 4.3. Your boss' friend would have unlocked prior to shipping the phone down but perhaps this was omitted. Your only options now would be to buy an unlock code online or perhaps the friend can contact AT&T to request the unlock code. If the device was off contract and is eligible for the unlock code, they would oblige the request. Otherwise, the code could cost between $18 - $30 online.
 

rikonor

New member
Dec 28, 2013
3
0
Thank you everybody.
I will use the service posted above.

I think it would be a good idea to make a sticky in this forum explaining that it is not possible at this point to downgrade from 4.3 (or is that just the boot loader).

Thanks again.
 

audit13

Inactive Recognized Contributor
Jun 4, 2012
12,911
5,052
Toronto
Thank you everybody.
I will use the service posted above.

I think it would be a good idea to make a sticky in this forum explaining that it is not possible at this point to downgrade from 4.3 (or is that just the boot loader).

Thanks again.

It is just the bootloader that cannot be downgraded, not the ROM.