yashsingh1/xdaforums huggingface dataset:
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] RockinRita:
Actually, when I first placed the T-mobile SIM card in it I was not able to use it so it did need to be unlocked from using on the Brightspot network.

---------- Post added at 12:02 PM ---------- Previous post was at 11:05 AM ----------

No superuser app installed and upon installing Root Checker I was able to confirm that it is not rooted. According to the phone itself and AT&T, you do only get 5 attempts to unlock via code before it is permanently locked to them. When I insert my T-Mobile or Brightspot SIM it prompts me for an unlock code. Upon entering the code the message I receive is that the code is not accepted.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] dawgdoc:
If you are not rooted, on the stock ROM, and stock recovery I do not know why it did not accept the code from AT&T. By the sound of it you have used all five tries. If so, can they reissue a code that is valid, or are all codes from them forever invalid? I wish I had further insight, unfortunately I don't, short of purchasing an unlock code.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] RockinRita:
Prior to today, I used up 4 of the 5 tries. I tried to get them to send me a new code after the code they sent me didn't work twice. The tech support rep I spoke with asked me to try again with her on the phone and I still got the error so she made note of my issue and that I tried again and then bumped it up to a supervisor who could research it and then issue a new code. Two days later I received an email stating the phone could be successfully unlocked with the code I was provided and I should try again in 24 hours. So that's just what I did and it still didn't work.

I've been waiting on my technologically inclined friend to free up so he could try to help me figure it out. In the mean time, I had just about given up but yesterday I decided to start researching more before using my last attempt. After coming upon this thread and you answering my questions, this afternoon I did a Google search just for the hell of it, for "how to unlock i747 without bricking" not thinking I'd get anywhere. And I found a user on AndroidCentral had the same problem with an unlock code not working about a year ago. About a month later another user responded with a method that worked for him. Several more users responded that the method worked for them too, including just last month. One user said it didn't work so I figured the odds were in my favor and I should give it a try. I tried and I'm in such disbelief- IT WORKED!!! It's a similar method to the second one mentioned here, except you still need an unlock code.

Here are the steps in case anybody else is still having the issue:

1. Make sure that wifi and flight mode is turned off

2. Go to the Dial pad and dial *#197328640#

3. Click on number [1] UMTS > [1] Debug screen > [8] Phone Control > [6] NETWORK LOCK

4. You will see 3 options

5. Please click on number [1] Perso Sha256 INFO, the screen will change slightly

6. Please hit the MENU button then when the menu pops up please carefully hit BACK to return to the previous screen

7. Please click on number [2] Perso Sha256 ON, the screen will change again to a one line message

8. Restart the phone on the screen by holding the power button and click RESTART

9. Reattempt to enter the code

10. Now the phone is supposed to accept the unlock code.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] DocHoliday77:
Thanks for posting your solution! And glad to hear you successfully unlocked!
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] dawgdoc:
I agree with DocHoliday77, thanks for posting your find [MENTION=4216689]RockinRita[/MENTION] . This is the first I have seen of this method. Hopefully others will find it with a search.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] RockinRita:
You're welcome. I too hope others find the solution i did whether it be here or there if/when they need it. I'm so happy that I got it unlocked but of course now I've got another issue with it lol. When I put my T-Mobile SIM in it registers that I'm on the network and I can make/receive calls and texts but I have no mobile data connection despite the settings showing it checked and the APN showing T-Mobile selected.

UPDATE: After checking mobile connection settings and APN settings multiple times I have been researching for hours on xda, Android Central, and even just Google for a way to fix the data connection issue. Eventually found my way to T-Mobile's support forums which gave directions for resetting the APN. I thought I had already done this, but it worked so I guess I neglected to do the obvious.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Can someone post a mirror? The links to the 4.1.1 firmware on the first post are dead. I have an old Bell S3 running CM 12.1 and I need to unlock it but nobody can tell me how. Bell says go to a mall kiosk and pay. Mall kiosk says they can't do it, go to Bell. Internet says dial *#197328640#, but that just gives an error message. Is there ANYTHING I can do to unlock this?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] nextmouk:
I'd say if you are running CyanogenMod, you are already unlocked.... did you try just putting in a sim card from other carrier?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] dawgdoc:
If your bootloader and modem are from android 4.3 or newer you can not downgrade to 4.1.1 w/o bricking your device.

If you are running CM 12.1 with no issues you are probably on a 4.4.2 bootloader, those are all NE6 or more recent. Downgrading any of these, since they are newer than 4.3, will brick your phone.

If you are absolutely certain you are on a bootloader that is safe for you to downgrade to 4.1.1, the stock roms are still available at sammobile for the i747M. You will need to flash them with Odin or Heimdall.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Yeah I just tried today at the WIND store. It asked for an unlock code. Although it might be moot anyway - apparently the guy said that all the stores are only accepting "penta band" now, and my old S3 is only a "quad band", except for Bell, who charges more than everyone else.

Allright thanks, I have no idea what bootloader I'm on, I'm the kind of person that just followed the list of the instructions exactly every time, while not understanding it completely. I think I was on 4.4 though, pretty sure I at least updated to 4.4 stock before ever rooting. Oh well.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] dawgdoc:
There is a playstore app that will check your bootloader and modem it is Phone Info *Samsung* by vndnguyen. If you have terminal emulator on your phone you can check without installing anything else. Enter each of these commands:

getprop ro.bootloader
getprop | grep version.baseband

I forgot to mention about the dialer code error message. Many of them only work if you are on the stock dialer, which wouldn't be present in CM roms. (I just ran the same code you entered and received an error message. I am on CM11.)

---------- Post added at 08:37 PM ---------- Previous post was at 08:24 PM ----------

@moeburn There are other sources for unlock codes. I have seen ebay mentioned with good comments, I just don't know which vendors are reliable. I think you must be on a stock rom with stock dialer to use the codes, whether from 3rd party or carrier.

Check and see if Bell can provide a code if you go back to a stock rom.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Yeah thinking back on it, I don't think I ever upgraded to 4.4 because I heard about it tripping a KNOX efuse, so I never did, I went straight from 4.2 to CM 12.1. Anywho the app you linked says my bootloader version is "i747mvldmf1", but I don't really know what that means. Anywho I have a feeling I might be on an old enough bootloader to downgrade so I can unlock, I don't suppose you can tell what bootloader I'm on from these screenshots can you?

Thanks for all your help! Unfortunately the folks at Bell weren't very helpful, they just said there was nothing I could do.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
[MENTION=4862334]moeburn[/MENTION], your phone is an i747 or i747m? I see d2att in the screen shot but the app may report the i747m as a d2att rather than a d2can.

One way to find this information would be to boot into download mode and look at the top of the phone. Also, with the phone in download mode, look for anything on the screen that says something about warranty bit or knox. If there is nothing about warranty bit or know, you should be able to flash a stock 4.1.1 ROM and use the free method to sim unlock the phone.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
It's an SGH-i747m

I found the bootloader info using that app, says I have the 4.1.2 bootloader, which sounds right, I remember never upgrading it past that because I heard if you did, you tripped some KNOX e fuse that made it so you couldn't go back. So I stayed at 4.1.2 until my warranty was out then went to cyanogenmod.

Is it not enough to know that my bootloader is 4.1.2, do I have to check the KNOX bit as well? It doesn't say anything about KNOX on the download mode, just this:
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
Since the screen says nothing about Knox and warranty bit, you should be able to flash the stock 4.1.1 i747m, use the free method to sim unlock the phone, and then flash the latest stock 4.4.2 or run OTA updates until you are running the latest stock ROM with the latest bootloader and modem.

Once updated, you can flash TWRP, and starting using the latest LP custom ROMs.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Woohoo, thank you!! And greetings fellow Torontonian!
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
I edited my post to say that the absence of knox or warranty bit on the download screen is a great thing!
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Oh good, thanks! So I've never downgraded firmware before - is there anything special I have to do, or can I just boot into CWM, factory wipe, and install the zip, and it will just work?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
You need to use Odin to flash the stock 4.1.1 ROM. The stock ROM can be downloaded from sammobile.com (which takes a long time). There may be links on XDA with faster download speeds. You just need the stock 4.1.1 ROM for the i747m, not i747.

After flashing, boot into recovery, factory wipe, and boot.

http://xdaforums.com/showthread.php?t=1739426

http://xdaforums.com/showthread.php?t=1968625
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] fattest:
i have a telus i747m which has been running various custom roms for the last two years, I don't recall what the last stock rom was. I tried flashing stock AT&T roms to do the unlock. With 4.1.1, I get the run EFS sync() option but that doesn't unlock the phone. On 4.1.2, there is no NW Lock NV Data INITIALLIZ option in the Network Lock menu so after doing PERSO SHA256 OFF nothing happens. Is downgrading to stock 4.1.1 via odin likely to brick my phone if I can't say for certain that it didn't receive 4.3 OTA? Thanks

Edit: My download mode screen is the same as moeburn's (no mention of knox). i installed phone info samsung and it says knox warranty void "warranty bit not found" and bootloader version "i747mvlalh1" --> ICS bootloader?? am i safe to downgrade to 4.1.1 stock image via odin?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] dawgdoc:
Since you have an i747M you should use a stock rom for that device, not one for the i747 (AT&T). Putting an i747 bootloader and modem on your device, as the stock roms do, would probably brick your device.

There is a Telus 4.1.1 rom available on sammobile, the shortname is LK4. (That would be and upgrade, not a downgrade :D )

If you were actually able to flash the AT&T rom proceed with caution in getting your device back to Telus stock. You don't want to brick it.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] fattest:
I've been flashing d2att roms on this phone for the past 2+ years and never had issues with bricking, and the radio has been perfectly functional. I neglected to mention that when I flashed the AT&T stock roms it was through TWRP recovery, not odin (if that's relevant). Since my bootloader is still LH1 which is apparently from ICS, I should be ok to use the image from sammobile to go to 4.1.1. thanks.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] DocHoliday77:
If I remember correctly, (at least on the T999), if you are on a 4.1.2 stock build, you only need to flash a 4.1.1 modem for this to work.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Alright, I got 4.1.1 flashed to my device, booted it up just fine, and that secret phone code actually WORKED this time! Woo! Now my only problem is that there are like 4 different sets of instructions on what to do in that menu, some of which require having an actual working sim card on hand, and I'm not sure if any of them worked. When I unlocked my old Atrix, it booted up with this small "UNLOCKED" text at the top left of the boot screen - should that happen on the S3 too? Because I don't see it.

And which one of these instructions am I supposed to follow?

Dail *#197328640#

Main Menu

[1] UMTS

[1] Debug Screen

[8] Phone Control

[6] Network Lock

[3]Perso SHA256 OFF

(after choosing this option, wait about 30 seconds, then go back one step by pressing the Menu button then select Back, now you are in [6] Network Lock

Set 2 of instructions:

Dial *#197328640#

Main Menu

[1] UMTS

[1] Debug Screen

[8] Phone Control

[6] Network Lock

[4] NW Lock NV Data INITIALLIZ. Wait one minute then power off the device.

Set 3:

Dail *#197328640#

Main Menu

[1] UMTS

[1] Debug Screen

[8] Phone Control

[6] Network Lock

[3]Perso SHA256 OFF

Wait a few seconds then press menu and go all the way back to the main menu.

[5] run EFS Sync()

Set 4:

1. Make sure that wifi and flight mode is turned off

2. Go to the Dial pad and dial *#197328640#

3. Click on number [1] UMTS > [1] Debug screen > [8] Phone Control > [6] NETWORK LOCK

4. You will see 3 options

5. Please click on number [1] Perso Sha256 INFO, the screen will change slightly

6. Please hit the MENU button then when the menu pops up please carefully hit BACK to return to the previous screen

7. Please click on number [2] Perso Sha256 ON, the screen will change again to a one line message

8. Restart the phone on the screen by holding the power button and click RESTART

9. Reattempt to enter the code

10. Now the phone is supposed to accept the unlock code.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] fattest:
Just used method 2, verified using two international sim cards.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Okay well now I have a new problem. I think I unlocked it properly, so I flashed TWRP and then CM 12.1 back on it. I just wanted to make sure I didn't break the phone in the process, so I got a SIM card from my Note 4 from the same carrier, Bell, and put it in the S3 (both the same size SIM). The S3 says "No SIM card found, emergency calls only". BUT phone calls work fine! I can make calls to and from the S3 to any number, not just emergency calls! But the LTE and internet ARE broken, they do not work.

So what the heck is going on here? What could cause Android to not find the SIM, but phone calls to work perfectly, but LTE/internet to be broken? It's a hell of a weird combo.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] DocHoliday77:
You probably just need to update your firmware. I don't use cm, but as I recall you are supposed to be running it on a 4.3 or newer bootloader. Otherwise multiple issues are often encountered.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
For the latest CM12.1, or any recent custom ROM releases, I would flash the latest stock ROM from sammobile. This will ensure that you have the latest modem and bootloader. It's the most tedious method but I believe it is the least risky.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Ah damn, that means I can't go back to 4.1.1 if it turns out I didn't do the unlocking process right. Well I hope I did! SHA256 INFO is set to 0!
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
Do you see anything about warranty bit or knox on the download screen? If you do, you need to buy an unlock code if the free method didn't work.

Looks like the free method did work for you so you just need to update the modem and bootloader.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Nope, no warranty bit stuff on the download screen, which is why I downgraded to 4.1.1 just a few posts ago, so I could go t hrough the free unlock process. It's just not like my Atrix where it gives you a big YOUR PHONE IS UNLOCKED! message at the top of the screen every time it turns on. Apparently if "SHA256 INFO" is set to 0, that somehow means my phone is unlocked. Which instills less confidence than an actual "your phone is unlocked" message, but oh well, to 4.3 we go!
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
I used to have an unlocked atrix hd and I only get the bootloader unlocked message at start up, never a sim unlocked message.

If you are not prompted for network unlock code when you boot up with a sim that is not from your carrier or its flanker brands, you should be good to upgrade to the latest modem and bootloader.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] fattest:
FWIW I followed more or less the same steps as moeburn (except flashed a telus stock rom to sim unlock) and now I've re-rooted and put latest TWRP and SlimLP with no issues using my local sim. Calls go through and I can connect to LTE network for data. My bootloader is still LK4 since I didn't do any OTA from the stock rom before flashing SlimLP.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
So it turns out SIM cards are tied to IMEI numbers, and that's why I can't just pop my Note 4's SIM in to the S3 to test it out, and also explains why I was able to make phone calls even though it said no sim detected. Everything worked perfectly fine, it turns out. I'm gonna leave it at 4.1's bootloader just to be safe though - there's no advantages to upgrading a bootloader anyway, right?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
If you want to run the latest ROMs, you'll need to update the modem which may require an updated bootloader. Always a good idea to match the bootloader and modem. Cross flashing may result in soft bricks. In the case of the i747, some combinations result in a hard brick.

I have never seen IMEIs tied to a sim card, at least with all Canadian carriers. Who is the carrier for the Note 4 sim?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
It's an updated modem but a 4.1.1 bootloader. It worked fine on CM 12.1 for over a year, I plan on going back to CM 12.1. Unless downgrading to the 4.1.1 also downgraded my modem, in which case I'm gonna have a hell of a time trying to find that modem file again.

It's just what Bell told us - that our SIM cards are tied to the IMEI number.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
Downgrading to stock 4.1.1 via Odin would have downgraded the modem too. It's the modem and stock dialler that, together, have the hidden menus.

I am also on Bell and have never had an imei tied to a sim card and I've used a lot of phones with the same sim card over the years without issue. These included phones that I unlocked from other carriers. I've used the LG G2, Nexus 4 (factory unlocked), Nexus 5 (factory unlocked), S3, Note 3 (Rogers), iPhone6 (Rogers), Note 2 (Koodo) , HTC Desire XL (Telus), and HTC One X (Rogers).
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Well turns out you were right - as soon as I tried to flash to 12.1, SIM card not detected. So I'm grabbing the latest rom/modem combo from here:

http://www.sammobile.com/firmwares/download/57672/I747MVLUFOB3_I747MOYCFOB3_BMC/

It will make it so I can't downgrade ever again, but hopefully I don't need to. And hopefully I can just do a factory wipe from TWRP and then flash the above file through ODIN and it will work fine, and then hopefully I'll be able to go to CM 12.1 from there!
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
I was also paranoid about upgrading and, since my warranty is over and my phone is sim unlocked, there was nothing really bad about upgrading to the latest 4.4.2.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Did I get the file and steps right though? I'm a bit of a script kiddie when it comes to this rooting/flashing stuff, and I'm not used to not having a set of bullet points laid out for me to follow. I already popped my soft-brick cherry today by trying to flash 4.1.1 via ODIN without doing a factory wipe first - got stuck at the Samsung logo without ever booting, but a factory wipe in stock recovery fixed it. I'd feel a lot better before doing this if I had a forum member telling me that the file I chose and the steps I mentioned appear correct (although I won't blame you if it doesn't work :P )
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
Yup you got the right file. I have used FOB3 files from all 3 carriers and cross-flashed them. All this seems to do is load different apps for different carries.

Here's what I always do to flash stock Samsung ROMs:

Download Odin 3.07 (I like Odin 307, has never failed me yet): https://www.google.ca/url?sa=t&rct=...5QWImOPDJboTA_V3D5S9eA&bvm=bv.107763241,d.dmo

Open Odin and place the tar.md5 file in the PDA box.

Uncheck everything in Odin except f.reset time.

Flash the file.

When you see the word RESET in the status window, remove USB cable, remove batter, replace battery, boot into recovery, factory reset, reboot.

If you want a stock rooted ROM, install TWRP and flash supersu.zip 2.49 from TWRP.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] dawgdoc:
That's what I did with my I747 when it was still on 4.1.2, left the bootloader alone and flashed the 4.1.1 modem. Of course, I have not had a sim from another carrier to test my unlock process.

Same here, but possibly even more so. I didn't upgrade to 4.4.2 until last month.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] moeburn:
Wait don't I need root to install TWRP?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
Root and custom recovery are two different things. Root is not required to install TWRP on the i747 and i747m. An unlocked bootloader, which both phones have, is required for TWRP and CWM.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] Khameleon:
No, you can flash it with Odin.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] intrepid24:
[MENTION=4673498]audit13[/MENTION] just to clarify, once on 4.4.2 there is no way to downgrade and therefore no way unlock the sim card?

do you recommend any commercial unlocking services?
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] audit13:
If the phone is on the 4.3 bootloader, you must buy a code.

A phone running a custom 4.4.2 rom on a 4.1.2 bootloader could revert to stock 4.1.1 rom and use the free method.

I just use the cheapest unlocker on eBay with good feedback.
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] baib88:
Hi guys, I am with Rogers, my S3 is on 4.4.2. Unrooted, if I root the phone, and switch to any custom Rom, can I downgrade to Stock Rom 4.1.1 to unlock the phone? how do I check my Bootloader version? many thanks,
[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] dawgdoc:
There are two common ways to check your bootloader and modem versions:

1) Playstore app by vndnguyen: Phone Info *Samsung*

2) commands issued in a terminal emulator, either an app or part of a custome recovery. The commands are:

getprop ro.bootloader
getprop | grep version.baseband

If you are on a bootloader that is from android 4.3 or newer then you are not able to downgrade to the 4.1.1 stock rom to carrier (sim) unlock the phone. In that case, 4.3 or newer bootloader, you can get an unlock code from your carrier. You will need to be on a stock rom with stock dialer for it to work. If you can not get a code from the carrier, there are third party resellers on ebay and elsewhere.