Develop Bugs

Seriously need some help. At the end of my patience with trying to update this thing

I'm really frustrated. I've been trying to update this Galaxy S3 for days now with no success. Currently I am running on Slimkat 7.0. It's sometimes slow and buggy and needs some updating.
For reference, this is the phone at its current state:
- Bootloader: i747ucalh9 (literally taken from the fail message when trying to update to any other bootloader)
- Modem/firmware (?): I747UCLH9
Here's what has happened, greatly summarized (note I'm using CM6.0.4.7 for all of these operations, and when I say "update", I mean "flash"):
- I tried updating to Slimkat 9 but received no signal. I gave up on it entirely for a while
- I tried installing various LP ROMs, including CM12.1.
- I had 12.1 running for a bit, but I had no connectivity. LTE, 3G,H+ nothing.
- I tried installing a newer modem (this thread. Finally at MJB, I could actually get connectivity in some of the newer ROMs (including Slimkat 9)... but it was very erratic. It would just randomly oscillate between LTE and 3G and H+. This also broke CM12.1 entirely.
- Again, the above problem was always present. Most of the LP ROMs would just bootloop me, though. The only one that worked was Cyanide L... which I didn't really like.
- I thought maybe the issue was the bootloader. My bootloader is still i747ucalh9. So I tried updating it to various bootloaders from here, but none of the updates will work. Literally, they give me error 6 or 7 and pretty much essentially tell me that I can't do it.
- So after repeating the cycle of "let me try to update this" several times and having the update fail on me, I'm still stuck at Slimkat 7 as the only thing that worked on LTE (note the past tense). Worse yet, I tried simply downgrading my modem to match my current bootloader version, but that made things worse than better. I am now stuck at 3G... which just recently went back to LTE. Talk about erratic.
- I also tried going full stock by flashing this: http://forum.xda-developers.com/showthread.php?t=2363882 But it expects 5 arguments for format, and got 3... or something. Failed hard.
So, I'm pretty much at the end of my rope here. I really might just go and grab a new phone at this point. I just really don't want to because this thing still works fine.... I guess I got unlucky and am at a version of the bootloader that is difficult to update from. I can't seem to go anywhere with this thing. Anyone have any ideas? Do I need to use a different recovery?
Thanks...

First and foremost, verify your bootloader. Install the Samsung phone info app, or in a terminal app or adb shell enter:
Code:
getprop ro.bootloader
If you're on any of the older bootloaders (the ones that do not end in MJB, NE4, or NJ1) there are two ways you can go (you probably will be given the age of your modem). If you're on any of the ones that end in MJB, NE4, or NJ1 you've got to be a lot more careful because downgrading them will hard brick your phone (Odin back to stock is not an option anymore).
Option 1: If you're on the older bootloaders, you can go to sammobile.com, grab the 4.1.1 firmware from there and flash it with Odin. Do not do this if your bootloader ends in MJB, NE4, or NJ1 (can't stress that enough). This will reset your phone completely to stock. You should now start getting OTA updates. They will be incremental updates, you'll have to take at least three or four to get up to date on bootloader and modem and they're big downloads. They will come every 24 hours, but you can cheat that by setting your system time forward 1 day to make them a little more rapid fire. This is a nice, safe way to get your firmware current. Once you're up to NJ1 firmware you can use Odin to flash a custom recovery and get back to custom ROMs; I'd recommend TWRP 2.8.6 if you're going to be flashing newer ROMs as CWM and Philz aren't as up to date and sometimes give problems with newer ROMs.
Option 2: I'm pretty sure your version of CWM is a big part of your problem. If you're going to be flashing lollipop you ought to update your recovery to TWRP 2.8.6; easiest way to get it is just use the Flashify app. I'd get that recovery up to date before messing with bootloaders too. Next get your firmware up to date. If your bootloader version is before MJB, then you have to start with MJB. Then update to NE4. Then update to NJ1. It has to be done incrementally, and the bootloader and modem must match on the newer firmwares, or you'll hard brick. This thread has recovery flashable MJB and NE4 bootloaders/modems; the bootloader and modem are packaged together in the same zip so you can't get out of sync. This thread has recovery flashable NJ1 bootloader/modem. This will get your firmware all up to date, and data should start behaving on newer kitkat and lollipop ROMs. This route is a lot more risky than the OTA route described above because of all the manual steps you have to take, but you could get it done quite a bit faster if you're confident in your abilities. Just read those linked threads very, very carefully and make certain you understand.
Good luck.

jason2678 said:
First and foremost, verify your bootloader. Install the Samsung phone info app, or in a terminal app or adb shell enter:
Code:
getprop ro.bootloader
If you're on any of the older bootloaders (the ones that do not end in MJB, NE4, or NJ1) there are two ways you can go (you probably will be given the age of your modem). If you're on any of the ones that end in MJB, NE4, or NJ1 you've got to be a lot more careful because downgrading them will hard brick your phone (Odin back to stock is not an option anymore).
Option 1: If you're on the older bootloaders, you can go to sammobile.com, grab the 4.1.1 firmware from there and flash it with Odin. Do not do this if your bootloader ends in MJB, NE4, or NJ1 (can't stress that enough). This will reset your phone completely to stock. You should now start getting OTA updates. They will be incremental updates, you'll have to take at least three or four to get up to date on bootloader and modem and they're big downloads. They will come every 24 hours, but you can cheat that by setting your system time forward 1 day to make them a little more rapid fire. This is a nice, safe way to get your firmware current. Once you're up to NJ1 firmware you can use Odin to flash a custom recovery and get back to custom ROMs; I'd recommend TWRP 2.8.6 if you're going to be flashing newer ROMs as CWM and Philz aren't as up to date and sometimes give problems with newer ROMs.
Option 2: I'm pretty sure your version of CWM is a big part of your problem. If you're going to be flashing lollipop you ought to update your recovery to TWRP 2.8.6; easiest way to get it is just use the Flashify app. I'd get that recovery up to date before messing with bootloaders too. Next get your firmware up to date. If your bootloader version is before MJB, then you have to start with MJB. Then update to NE4. Then update to NJ1. It has to be done incrementally, and the bootloader and modem must match on the newer firmwares, or you'll hard brick. This thread has recovery flashable MJB and NE4 bootloaders/modems; the bootloader and modem are packaged together in the same zip so you can't get out of sync. This thread has recovery flashable NJ1 bootloader/modem. This will get your firmware all up to date, and data should start behaving on newer kitkat and lollipop ROMs. This route is a lot more risky than the OTA route described above because of all the manual steps you have to take, but you could get it done quite a bit faster if you're confident in your abilities. Just read those linked threads very, very carefully and make certain you understand.
Good luck.
Click to expand...
Click to collapse
Thanks a lot for the help! I actually did/tried a majority of this an hour or two before you posted that, except the latest firmware update link you supplied. I knew it existed and I had seen that thread before, but I couldn't dig up the link again before I had to go to work. Thing is I kind of wanted to avoid Odin for some reason but I finally gave up and used it. And yeah I already knew my bootloader version. The phone told me when it failed to update the bootloader lol.
Here's what happened thus far:
- I used Odin to flash the sammobile 4.1.1. The flashing worked just fine, but booting into it did not. It hung on the Samsung logo. So, OTA updates were out the window.
- I have no idea why, so I just used Odin to flash TWRP onto it afterwards (from here)
- I tried one of the ROMS. Data still didn't work.
- I used the thread you linked to update to MJB bootloader and whatnot. The update went fine.
- Tried another few ROMs. Data worked, but LTE was still erratic.
- Updated to NE4 and then grabbed the deoxed stock ROM.
- The deoxed stock rom failed to boot (stuck at ATT globe logo). For some reason my phone can't use stock ROMs.
- So again used Odin to put TWRP onto the phone
- Installed various LP ROMS. Again the data was erratic and plus the battery life was horrid.
- Tried getting the ktoonsez kernel. My service was murdered.
- Gave up on LP. Tried Slim 9.0. Erratic data.
- Tried Liquidsmooth 4.4.4 instead.
Currently that's kind of where I'm at. The LTE data works fine (takes a bit to get up and running after reboot though) and thus far everything is okay (though that can quickly change considering I haven't done much of anything), so I don't even know if I want to mess with it anymore. It looks like this specific ROM includes a custom kernel. So I'm guessing it's an incompatibility between the kernel and the firmware version on the other ROMs. It seems like most of the LP roms have horrible battery life (back of my phone feels like a furnace on them), so I'm not even sure if I want to do that last firmware update to use them.
It'd be kind of nice to use the OTA but apparently my ability to go stock in any form or fashion is just totally borked.
Thanks for the post though, that's pretty gold. I'm sure someone in a situation like me where they have a super old firmware will find this thread of some use as it has actual instructions and links to what you need to do to get up and running. Before you posted that, I had to go digging around pretty much everywhere figuring out what and where was going wrong.

Glad you've got it mostly working.
You might have been able to get that stock ROM to boot if you had booted into the stock recovery and run a full wipe. Touchwiz ROMs can be tough to get running after being on AOSP. As a general progression try to format internal storage with TWRP (the wipe where you have to type "yes" to confirm), if that doesn't work try a wipe with Philz, and if that doesn't work nothing, not even Odin, is effective as a wipe in the stock recovery.

Thanks for typing all this out I believe it will help me put cm12.1 official on a friends phone.
Are these the steps?
1) verify latest software
2) twrp via Odin
Alt 2) root via apk then use rashr or similar to flash twrp
3)wipe
4)In twrp install official d2att from cm website
5) install current gapps
6) profit
I'm not new to this at all but I've never even touched an att gs3 and I know most devices have their quirks and I don't want to brick.
Also does towel root work on this? I don't mind Odin but I can do this on the fly I think if I can attain root.
Sent from my DROID RAZR M using XDA Free mobile app

mrkhigh said:
Thanks for typing all this out I believe it will help me put cm12.1 official on a friends phone.
Are these the steps?
1) verify latest software
2) twrp via Odin
Alt 2) root via apk then use rashr or similar to flash twrp
3)wipe
4)In twrp install official d2att from cm website
5) install current gapps
6) profit
I'm not new to this at all but I've never even touched an att gs3 and I know most devices have their quirks and I don't want to brick.
Also does towel root work on this? I don't mind Odin but I can do this on the fly I think if I can attain root.
Sent from my DROID RAZR M using XDA Free mobile app
Click to expand...
Click to collapse
Yep. You've got it. If you're on the latest and greatest firmware I think the towelroot exploit has been patched, unless geohot has retaken the lead in that arms race.
Easiest way to root on this phone since the bootloaders are unlocked is to just use Odin to flash a custom recovery then use the custom recovery to flash SuperSU. There's just a little trick to it. Store SuperSU.zip somewhere on your phone before flashing the custom recovery. Uncheck everything but f.reset time when you use Odin; don't let it auto reboot. Upon success pull battery. Replace battery and boot straight into recovery with vol up + home + power. If you mess up and boot into unrooted stock ROM with a custom recovery it will get overwritten with a stock recovery and you'll have to Odin custom recovery back onto it and try again.
I would do this to root your stock ROM just to execute this command in a terminal app or adb shell before any more serious flashing:
Code:
su
reboot nvbackup
That fixes a derp and gives you a working efs backup on a few backup partitions built into your phone instead of a blank one. Highly recommended before doing any ROM flashing. This will just look like a pretty normal reboot. You might see a quick flash of tiny blue text if you're watching for it.
Then you're ready to make a nandroid backup (just in case), wipe, and flash away. Take a look at LiquidSmooth if you're looking for a good lollipop ROM.

Nice... So the recovery partition gets rewritten every boot up until a custom ROM is installed and the efs can disappear... This is why you always ask questions.
Thanks for the suggestion on the ROM but I think I'll stick to official cm12.1 it's not my phone and that should be a nice readily updatable bland flavor of lollipop.
Sent from my DROID RAZR M using XDA Free mobile app

mrkhigh said:
Nice... So the recovery partition gets rewritten every boot up until a custom ROM is installed and the efs can disappear... This is why you always ask questions.
Click to expand...
Click to collapse
At the Android 4.3 update it was noticed that flashing a custom recovery would be overwritten by the stock recovery on the initial reboot unless following the method Jason described. Another solution was to delete two lib or .so files. On devices still on stock recovery, stock recovery does not overwrite itself.
There is a blank EFS partition on the device intended for a backup. The nvbackup command populates that partition with an image which will rebuild your EFS if it is lost during a modem update or ROM flash. The loss of EFS does happen. I believe wanam, of the xposed module fame, created an EFS backup tool for Samsung devices. I don't believe he updates it any longer because he rolled the functionality into a partition backup tool, the later is in the PlayStore listed under a different creator name, yet it's still him.

So I'm finally going to take the plunge, and update my boot loader/modem.. I never messed with it because all the Roms I used always worked.. I want to try lollipop, but due to old bootloader my phone won't boot with those Roms..
I'm on UCDLK3 bootloader/modem.. I know I have to upgrade to MJB, NE4, then NJ1 in that order in increments..
So my question: can I upgrade from LK3 straight to MJB with out any problems?? Or is there something I need to flash before I can get to MJB?? I think I can go straight to MJB, but better safe then sorry..
I know downgrading after upgrade most likely will brick.. Any information is appreciated... Oh, its an ATT I747..

coolwhipp420 said:
So I'm finally going to take the plunge, and update my boot loader/modem.. I never messed with it because all the Roms I used always worked.. I want to try lollipop, but due to old bootloader my phone won't boot with those Roms..
I'm on UCDLK3 bootloader/modem.. I know I have to upgrade to MJB, NE4, then NJ1 in that order in increments..
So my question: can I upgrade from LK3 straight to MJB with out any problems?? Or is there something I need to flash before I can get to MJB?? I think I can go straight to MJB, but better safe then sorry..
I know downgrading after upgrade most likely will brick.. Any information is appreciated... Oh, its an ATT I747..
Click to expand...
Click to collapse
Since you are on LK3 you may want to considr applying the free sim/carrier unlock method before upgrading; that is if you are on stock LK3 and you have not previously carrier unlocked your device.
There was an OTA release for the MG2 stock ROM, I believe that was 4.1.2. You may want to go to that before MJB. Did you make the nvbackup suggested by Jason?

Why would I do a carrier unlock, if I'm not switching carriers?? And if I do it, will I be able to use the same carrier?? Just seems like a waisted step for me.. But idk..
Jason's first post, option 2 is how I was planing to update.. And no, I haven't done the nvbackup yet.. How would I apply that backup if things go wrong? Not really sure what a nvbackup is..
Any information is appreciated..

coolwhipp420 said:
Why would I do a carrier unlock, if I'm not switching carriers?? And if I do it, will I be able to use the same carrier?? Just seems like a waisted step for me.. But idk..
Jason's first post, option 2 is how I was planing to update.. And no, I haven't done the nvbackup yet.. How would I apply that backup if things go wrong? Not really sure what a nvbackup is..
Any information is appreciated..
Click to expand...
Click to collapse
There is a command to manually trigger the restore routine. I think it's
Code:
reboot nvrestore
but don't hold me to that. I'd never execute that command except if in dire need. The problem with this phone is there is an automatic routine that can be triggered in the event of a bad flash that will overwrite your nvram with the backup, even if the backup is blank. I don't think the backup stores anything modem specific, but I've never been able to confirm that. So I've always done it again after updating modems (only had to once).
Having the phone sim unlocked can be nice if you plan on traveling internationally. Otherwise, potential future carrier hopping or added resale value are the only reasons to do it.

coolwhipp420 said:
Why would I do a carrier unlock, if I'm not switching carriers?? And if I do it, will I be able to use the same carrier?? Just seems like a waisted step for me.. But idk..
Jason's first post, option 2 is how I was planing to update.. And no, I haven't done the nvbackup yet.. How would I apply that backup if things go wrong? Not really sure what a nvbackup is..
Any information is appreciated..
Click to expand...
Click to collapse
If you will never be switching carriers, nor ever sell/give/trade the phone to someone who will switch, then it is an unecessary step to do the carrier unlock.
I see Jason beat me to answering both of your questions.

Need advice n7105 strange knox bootloop with every rom but 4.1.2 stock after cm10.1

Hello,
I'm a noob but usually try to fix this kind of issues on my own, looking at the boards, following tutorials, learning, but this time I think I'm not able to find a solution on my own so I'm asking for advice here.
Some time ago I installed cyanogenmod 10.1 on my Note 2 LTE and was happy with it for some month, than last week I tried to upgrade to cm12.1 It worked but there where some issues and bugs, mainly I wasn't able to swap internal/external sd cards.
So I decided to go back to latest available stock rom 4.4.2 from sammobile.
Here is where the problem starts. The stock 4.4.2 resulter in a bootloop, tried cache/dalvik/factory reset, flash again, whipe again.. nothing.
The phone is not able to get past the white label "Samsung Note 2 gt-n7105" screen. It goes black than the white label again and again.
It doesn't even get to the Samsung animated logo.
Ok bottloop, no problem, try to flash again something else.
I tried different Custom roms, different kernels, different flashing methods. I can flash anything with no problem but every time a get a bootloop.
During the various attempts knox fired, but I don't care. I don't know if this could be the cause.
Actually the only firmware that works is the original oldest STOCK 4.1.2, every other stock firmware past that or any custom rom is bootlooping the same way. To fix I only can reinstall stock 4.1.2 with odin.
I really need any advice or hint.
At the moment my goal is to get at least to stock 4.3 but I cant.........
Thanks!

When you first bought your phone, did it come with Knox?

ErnestChia said:
When you first bought your phone, did it come with Knox?
Click to expand...
Click to collapse
nope it doesn't existed before, but now I can see it when I boot in download mode "knox warranty void:1"

Try to get the latest firmware available via kies ,that worked for me
http://forum.xda-developers.com/showthread.php?t=2088809/[URL]

From what you've described, I think the Stock ROM 4.4.2 from Sammobile contained a bootloader update. So when you flashed this ROM, it updated your bootloader from the non-Knox version to the Knox version.
I am very unfamiliar with the technical details of Knox, but I think the new Knox bootloader is causing your bootloop problem.
However, I don't know why 4.1.2 works when everything else doesn't work!
Can you check the Stock ROM 4.4.2, and see whether it really contains a bootloader update?

mysuperdonghae said:
Try to get the latest firmware available via kies ,that worked for me
http://forum.xda-developers.com/sho...can flash cm10, 11 and 12 with no issue too..
Click to expand...
Click to collapse

misthero said:
I think so, there is a boot.im, anyway I also discovered that I can flash cm10, 11 and 12 with no issue too..
Click to expand...
Click to collapse
Since a boot.img is present, it means that it would flash your boot partition. So now we know for sure that when you attempted to flash the Stock ROM 4.4.2, your bootloader was changed to the Knox version.
So the lesson here is: before you flash anything via ODIN, always check to see if there is a bootloader update. Usually you don't want to be changing the bootloader on your phone.
***
So now there are 2 possible ways to reach your goal:
1) Keep your new bootloader and see whether you can get Stock 4.3 or Stock 4.4.2 running on your phone
2) Try to restore your old bootloader
As I said earlier, I'm not familiar with the technical details of Knox, so I'm not sure how to get Stock 4.3 or Stock 4.4.2 running on your phone when your Knox indicator is already 0x1. You need someone else to help you.
And you can only restore your old bootloader if you happen to have made a copy of your boot partition before you flashed the Stock ROM 4.4.2. Even if you did have a copy of your original boot partition, I'm not confident with helping you to restore your old bootloader. You need someone else to help you in this case too.
Conclusion: I don't think I can help you to solve your problem I'm sorry. Hopefully someone else who is more of a pro than me will come along to help you out.
Good luck!

Please help me , any good soul out there willing to provide a good hand ?

First of all thanks for passing by my thread , my case is a really strange one , i have an galaxy s6 edge t mobile with DOJC wich is the lastest build , i unlocked thru a direct cable software method provided by unlockbase , as always i rooted the phone , i used unikervel ver 8.0.0.2 and did the unlock , problem is that the fingerprint stopped working forever eversince , and no matter what i do it just displays the same error " an error ocurred with the fingerprint sensor " now i tried everything in my knowledge and google researching , tried the erasing cache method , flash stock bootloader and system plenty of time , downgraded a tons of times even installed a custom rom to see if there was any change , it was working before so im wondering what could happen , ive done this with multiple s6 edge with older builds and never has happened to me , today i downgraded againg do DOl1 and something more weird happened , the imei is there as always but the numbers after the slash are gone says /null now this hasnt affected anything but i dont know why it happened , the second werdiest thing its that the sensor version , in the secret menu for testing everything gives me a null version , does anybody know what can i do to get my fingerprint working againg ?? every lil comment would help thanx a lot

Sorry to hijack his thread. But I see you got root on the tmobile dojc firmware.
I got the edge today and have been going through post trying to figure out what needs to be done.
I know that two needs to be flashed through Odin. Not sure on the version tho.
And that a kernel needs to be flashed then the SU.zip
My question is what kernel. No one specifically says which one to use for the DOJC firmware and the BL option in Odin is where the kernel would go correct?
So
Odin -install tarp
Odin- kernel
And then flash the su zip in twrp
Am I missing anything ?
And hope somebody chimes in to help with your issue at hand ! Good luck

There no need my friend , just flash unikernel Ver 8.0002 thru odin adn the phone will be instantly root
epicroot said:
Sorry to hijack his thread. But I see you got root on the tmobile dojc firmware.
I got the edge today and have been going through post trying to figure out what needs to be done.
I know that two needs to be flashed through Odin. Not sure on the version tho.
And that a kernel needs to be flashed then the SU.zip
My question is what kernel. No one specifically says which one to use for the DOJC firmware and the BL option in Odin is where the kernel would go correct?
So
Odin -install tarp
Odin- kernel
And then flash the su zip in twrp
Am I missing anything ?
And hope somebody chimes in to help with your issue at hand ! Good luck
Click to expand...
Click to collapse

Installing stock kernel should make your fingerprint scanner work. Once you change the kernel, poof no scanner.
Pp.

Thanx for the reply my friend i did that alredy still does not work i think it just broke the moment i rooted coincidentially
PanchoPlanet said:
Installing stock kernel should make your fingerprint scanner work. Once you change the kernel, poof no scanner.
Pp.
Click to expand...
Click to collapse

I recall reading somewhere that not tripping knox when rooting had something to do with scanner not working.
Did you "not" trip Knox?
Pp

Have had this happen with some of my customers. Flashing stock firmware solved the issue.
Can download stock OJC here
STOCK OJC DOWNLOAD
I recommend Odin 3.10.6
ODIN 3.10.6

Can I go from 4.0.4 to 4.1.1 or higher right away?

Hi all, new comer to the S3 here but not new to flashing etc. I just wanted to get a few things straight before I went ahead.
1. I downloaded and used Mskip unified android toolkit. I rooted and flashed twrp recovery to my S3.
I am on I747UCALG1 4.0.4 and I just wanted to know if I can flash the 4.1.1 build ATT-I747UCDLK3 that I found here straight away in odin. I know some sammy phones are drama queens when it comes to new bootloaders etc. Will the new build update the bootloader or should I do this separately.
Or should I just download a rom from the development section and flash it in twrp or won't that work and I need to flash a new bootloader first then flash the newer roms.
Thanks for any help and yes I did search around but only found questions regarding downgrading.

Bro, remember my strong advice - don't go higher.
Battery life goes worse with every update. I wish I never did it.
But if you want to try something new, try OctOs

The problem I'm having right now is that my wifi keeps on scanning but does not find any networks although I am 2 feel from my router. This phone really was my Gfs that went crazy and I changed out the mainboard so I'm just running it as a back up.

Personally, I would flash stock 4.1.1 from sammobile.com and sim unlock the phone using the free method if the phone is sim locked. Once sim unlocked, I suggest running OTA updates until the phone is running the latest stock ROM. Once it is running the latest stock ROM, flash twrp, take a nandroid backup, and then flash a custom ROM if you want.
Note: once the phone is running the latest bootloader, you cannot downgrade the bootloader.

Would be hard to do an OTA since I cannot connect to any wifi networks.

if youre talking upgrading bootloader/modems , and cannont do as @audit13 suggests , and cannot connect to wifi or use/have enough data ; then i would suggest upgrading incrementally.
"err on the side of kindness"

Is wifi disabled on the phone?

audit13 said:
Is wifi disabled on the phone?
Click to expand...
Click to collapse
No it is on and scans for networks but it does not show any, even if I add a network manually it does not connect. I read somewhere that I need a newer bootloader in order for the wifi to work. Does anyone have the newest bootloader for me to flash and try this out on?

mrrocketdog said:
whats your current bootloader and modem.? if dont know u can download app called "samsung info" from play store that will tell.
heres the xda thread
http://forum.xda-developers.com/showthread.php?t=2609045
"err on the side of kindness"
Click to expand...
Click to collapse
"err on the side of kindness"

Do the last 4 characters of the modem match the last four characters of the bootloader?
For wifi to work properly, it is best to match the bootloader to the modem and vice versa.

Can't connect to certain Wi-Fi, need help

I just joined in the past few days because I decided to try different ROMs on my i747. This is my 1st ever post, and I thought I'd try out this rooting and flashing that I'm missing out on.
First of all, THANKS to EVERYONE that posts here for all of the help given to me and that others have used. Nice to see people helping out other people in such ways.
Second, I have successfully put a few different ROMs on my i747 over the past few days and can't believe how easy it was. I was always scared to do it. I decided since the thing was just sitting in a drawer not being used "What's the risk?"
Third, my actual issue...No matter what ROM I have on the i747, it will not connect to Wi-Fi at my work. FYI, I work (in IT ironically) in a very large company with hundreds of access points around the campus. So I know it is not the network, as we would have others with the same issue. It connects to all other (that I've tried so far) Wi-Fi networks with no issues.
I just don't understand all the terms bootloader, firmware, kernel, modem etc. I read decriptions (on here) trying to explain and I just can't grasp it.
I was on stock with whatever the last OTA update from AT&T was. I updated the boatloader (I believe) from NE4 to NJ1 to NJ2 using this thread. At least, I'm assuming I did it right. Nothing failed and the Phone Info app looks like it worked. https://forum.xda-developers.com/galaxy-s3-att/general/ucuemjb-to-ucufne4-firmware-update-t2808654
Anyone can give me any tips on what I need to do to possible get this working? It's not really a huge deal breaker, it's just bugging me as to why it isn't working.
Thanks in advance!

You upgraded the modem/baseband software when updating the bootloader?

audit13 said:
You upgraded the modem/baseband software when updating the bootloader?
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I'm guessing no. How do I do that? Don't want to brick it.
I found this link, but what firmware am I on? How do I tell?
https://forum.xda-developers.com/galaxy-s3-att/general/modem-4-4-2-modems-i747-i747m-t2856577

Did you flash the zip or did you flash aboot.mbn? If you flashed the zip, the bootloader and modem would have been updated at the same time.

audit13 said:
Did you flash the zip or did you flash aboot.mbn? If you flashed the zip, the bootloader and modem would have been updated at the same time.
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I flashed the zip.

So an unrooted stock ROM also refuses to connect?

audit13 said:
So an unrooted stock ROM also refuses to connect?
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I don't know how to go back to stock.