[Snap. +] Guide for Flashing Standard FW, Carrier Switching, and Flashing Unlocked FW

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Mike15678

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Jun 18, 2017
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Hello, there. This is my second guide, so please forgive me if it looks a bit weird. But without further ado I present you with my Official [Snapdragon] Guide for Flashing Standard Firmware, Carrier Switching, and Flashing Unlocked Firmware for the S8+.[/SIZE]
Here are some useful reminders:
All download links are at the bottom of this post.
Make sure you follow the "Prerequisites For Anything You decide To Do In This Guide" section.
Don't copy quotation marks, unless I tell you to in this guide.
You will need a Windows computer in order to utilize the software provided. Mac users can use Boot Camp to dual boot their machines. Using WINE is not recommended.
This is an S8+ guide, not an S8 guide. Go to https://xdaforums.com/galaxy-s8/how-to/snap-guide-flashing-standard-fw-carrier-t3625817 to check out my S8 guide.
WARNING: Anything you do in this guide will erase your phone completely. It's recommended that you back up before you do anything and that you remove your Google account from your phone (so you don't have to go through FRP).
Note: Flashing to stock from Unlocked firmware requires you to follow the "Carrier Switching" section (which eventually requires you to follow the "Flashing Standard Firmware" section) and do as it says, unless the CSC code of your carrier is currently active. You can check this by going into Recovery Mode by holding the Power button, Bixby button, and Volume Up button until you see a dark blue screen with text saying that the firmware is being updated (it's not actually). Once it transitions to a black screen, your active CSC will be on the bottom log (three characters). If your CSC code is already your carrier's, then just follow the "Flashing Standard Firmware section. But for anything you decide to do, you must follow the "Prerequisites for anything you decide to do in this guide" section.

Disclaimer:
I am NOT responsible for any damage done to your device if you decide to use this guide.

Prerequisites for anything you decide to do in this guide (Required):

Standard Odin
Samsung Drivers
Steps:
1) Uninstall Samsung Switch and/or Samsung Kies, if present on your computer. This helps removes any conflicts with Odin.
2) Extract the Samsung Driver zip and the Odin zip to somewhere safe on your computer.
3) Double click on the extracted "SAMSUNG_USB_Driver_for_Mobile_Phones" executable (SAMSUNG_USB_Driver_for_Mobile_Phones.exe).
3) Navigate to your extracted Odin folder and double click on the Odin configuration file (Odin3.ini).
4) You should have entered Notepad (or your preferred note editor). Find the "[ButtonOption]" section.
5) There should be a setting there called "UMS/PATCH". Change the value of "0" to "1" so it becomes "UMS/PATCH=1".
6) Press the "Ctrl" key and "S" key on your keyboard to save the file.
7) Go ahead and close out of Notepad.


All About Bootloaders (Required Reading):
As Wikipedia puts it, “A boot loader is a computer program that loads an operating system or some other system software for the computer after completion of the power-on self-tests.” In other words, a bootloader is what loads you operating system. In most Samsung phones (including the S8 and S8+), there’s an e-fuse that prevents downgrading of the bootloader. This means any firmware or firmware update containing a lower Bootloader version than the one you have, will FAIL to be applied. There is really no way to circumvent this.
(From what I can tell) S8+ firmware released since December are Bootloader v2, while anything before that month is Bootloader v1. In the next section, I’ll be explaining how to properly identify your current Bootloader version.

How to identify Bootloader version (Important):
Steps:
1) Open “Settings” on your phone.
2) Scroll down to “About Phone”.
3a) If you are on a standard, carrier firmware, under “Baseband version” you should see something similar to this: “G955UXXXXXXXX”.
3b) If you are on an unlocked firmware, under “Baseband version” you should see something similar to this: “G955U1XXXXXXXX”.
4) No matter which firmware you're on, the fourth “X” would be either a “1” or a “2”, which means you will have either Bootloader version 1 or Bootloader version 2, respectively.

Note: As stated in the last section attempting to flash firmware that contains Bootloader v1 onto a phone that already has Bootloader v2, will fail. You can update a phone on Bootloader v1 to a firmware that has Bootloader v2, however.
How To Download Firmware with Updato:
Note: This is an add-on section for any part of the guide that requires you to download specific firmware.
Updato can download old or new firmware for phones, therefore you can download Bootloader v1 or Bootloader v2 firmware. However, Updato tends to be much slower than SamFirm, therefore its recommended that you use SamFirm if you’re willing to download Bootloader v2 firmware. You should only use Updato if you need to download Bootloader v1 firmware.
Steps:
1) Go to http://fw.updato.com
2) Type in your Model Number (SM-G955U for carrier S8+’s; Firmware for unlocked S8+’s can be found in the “Downloads” section)
3) Find firmware for your specific region.
Here are some common Region codes:
BST Boost
VZW Verizon
ATT ATT
USC US Cellular
ACG C Spire
TMK MetroPCS
VMU Virgin Mobile
TFN Tracfone
XAS Sprint
TMB T-Mobile
XAA Unlocked US
SPR Sprint
CCT Xfinity Mobile
AIO Cricket

4) Download it somewhere safe onto your computer.

How To Download Firmware with SamFirm (Faster):
Note: This is an add-on section for any part of the guide that requires you to download specific firmware.
SamFirm can only download the latest firmware for phones, therefore you’ll be downloading a Bootloader v2 firmware (which means once you flash it, there's no going back to Bootloader v1 if your phone is currently on that version). SamFirm tends to be much faster than Updato for downloading firmware, since the firmware is downloaded directly from Samsung.
Prerequisites:
SamFirm (SamFirm_v0.3.6.zip):https://xdaforums.com/galaxy-tab-s/general/tool-samfirm-samsung-firmware-t2988647
Steps:
1) Download “SamFirm_v0.3.6.zip”. Make sure you’ve installed all of its prerequisites listed on the page, such as “.NET Framework 3.5”, “Microsoft Visual C++ 2008 Redistributable Package (x86)”, and “Microsoft Visual C++ 2010 Redistributable Package (x86)”
2) Extract “SamFirm_v0.3.6.zip” somewhere safe onto your computer.
3) Double-click on “SamFirm.exe” to open it.
4) Enter your Model Number and 3-character Region code.
Here are some common Region codes:
BST Boost
VZW Verizon
ATT ATT
USC US Cellular
ACG C Spire
TMK MetroPCS
VMU Virgin Mobile
TFN Tracfone
XAS Sprint
TMB T-Mobile
XAA Unlocked US
SPR Sprint
CCT Xfinity Mobile
AIO Cricket

5) Make sure you’ve ticked the “Manual” checkbox.
6) Input your “PDA”, “CSC”, and “Phone” strings into their respective slots based off the information found from fw.updato.com for your latest specific firmware. Please note that the “CSC” slot is not the same as the same as the “Region” slot; the “CSC” slot should have a long string inputted.
7) Tick the “Binary Nature” checkbox.
8) Click the “Check Update” box.
9) Your firmware should now appear. Make sure the “Check CRC32” and “Decrypt Automatically” checkboxes are ticked.
10) Click on the “Download” box, choose where you want to store the firmware, and relax for a while.

Flashing Standard Firmware:
Prerequisites:
What's listed in the "Prerequisites For Anything You Decide To Do In This Guide" section.
Firmware you want to flash; follow the “How To Download Firmware with SamFirm” or “How To Download Firmware with Updato” section, if you need firmware.
Steps:
1) Extract your downloaded firmware to somewhere safe on your computer.
2) Turn off your S8+.
3) Once off, hold the Power button, Volume Down button, and the Bixby button until you see a blue screen on your phone.
4) Press the Volume Up key to enter Download Mode.
5) On your computer, navigate to your extracted Odin folder.
6) Double click on the "Odin3 v3.12.7" executable (Odin3 v3.12.7.exe)
7) Connect your phone to your computer with your USB cable.
8) You should see Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
9) Now it's time to add your firmware files that were extracted earlier. Individually add an appropriate firmware file for each box on the right. The "BL" box will require a firmware file that starts with "BL", the "AP" box will require a firmware file that starts with "AP", the "CP" box will require a firmware file that starts with "CP", the "CSC" box will require a firmware file that starts with "CSC" (DO NOT USE THE "HOME_CSC" file for the "CSC" box), the "UMS" box will require a firmware file that starts with "USERDATA". The "AP" and "USERDATA" files will take the longest for Odin to load because of their size.
10) Go to the "Options" tab and make sure that only the "Auto Reboot" and "F. Reset Time" checkboxes are ticked.
11) Go back to the "Log" tab.
12) Click the "Start" button on bottom right.
13) Sit back and relax for a while. Odin will output what is being flashed in the "Log" and on a box in the top left.
14) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
15) Once the flash finished, disconnect your phone from your computer.
16) Your phone will do an erase at this point, so don't mess with your phone until you reach the setup screen.
17) PROFIT. Follow the setup on your phone and you're good to go.

Carrier Switching:
NOTE: Doing this process does NOT unlock your phone for use on other carriers.
Prerequisites:
What's listed in the "Prerequisites for anything you decide to do in this guide" section.
S8+ Factory Binary (either Bootloader v1 or Bootloader v2)
Prince Comsy version of Odin
Google Platform-Tools (ADB)
Canadian HOME_CSC (either Bootloader v1 or Bootloader v2)
Steps:
1) Extract the downloaded S8+ Factory Binary, the Prince Comsy version of Odin, Platform-Tools, and the Canadian firmware, to somewhere safe on your computer.
2) Turn off your S8+.
3) Once off, hold the Power button, Volume Down button, and the Bixby button until you see a blue screen on your phone.
4) Press the Volume Up key to enter Download Mode.
5) Navigate to the extracted Odin (NOT PRINCE COMSY) folder.
6) Double click on the "Odin3 v3.12.7" executable (Odin3 v3.12.7.exe).
7) Connect your phone to your computer with your USB cable.
8) You should see Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
9) Click on the "AP" box and navigate to the extracted Factory Binary folder. Double click on the file the starts with "COMBINATION".
10) Wait for Odin to load the file.
11) Go to the "Options" tab and make sure that only "Auto Reboot" and "F. Reset Time" checkboxes are ticked.
12) Go back to the "Log" tab.
13) Click the "Start" button on bottom right.
14) Odin will output what is being flashed in the "Log" and on a box in the top left.
15) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
16) Leave your phone connected and let your it reboot into the 'factory binary homescreen' (Basically, the equivalent of a home screen on a regular S8+).
17) Navigate to the "platform-tools-latest-windows" folder. Once you’ve navigated to where “adb.exe” is located, click the address bar on the top and press “Ctr+C”.
18) Open cmd.exe through “Run” (Windows key + R)
19) Type in “cd /d “<copied folder location>”” (Make sure you’re putting the folder location in quotes and not the command itself)
20) Type in "adb reboot bootloader". Leave ADB open.
21) Your phone will reboot into Download Mode. Your device should still be connected and ADB should also still be open.
22) Navigate to the Prince Comsy version of Odin and double click on the "Odin PrinceComsy" executable (Odin PrinceComsy.exe).
23) You should see the Prince Comsy version of Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
24) Click the "CSC" box and navigate to the “HOME_CSC” file you downloaded.
25) Double click on the file that starts with "HOME_CSC" (DO NOT USE the "CSC" file for the "CSC" box). It should load quickly.
26) Go to the "Options" tab and make sure that only "Auto Reboot" and "F. Reset Time" are ticked.
27) Go back to the "Log" tab.
28) Click the "Start" button on bottom right.
29) Odin will output what is being flashed in the "Log" and on a box in the top left.
30) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
31) Once your phone reboots, you will see an "IME" button on the 'factory binary homescreen (It’s on the bottom). Tap on it.
32) A number pad should appear. Type in "*#243203855#".
33) A menu will pop up. Scroll down until you find an "XAC" option. Tap on it and tap "Install".
34) Your phone will reboot. Once it reaches the 'factory binary homescreen', go to ADB on your computer and type in "adb shell".
35) *LOOK A TINY BIT BELOW!* Type in "echo "XXX" > /efs/imei/mps_code.dat" (the quotation marks that surround the X's are used, but not the ones that surround the whole command... you know that by now- right?) and REPLACE XXX with your preferred CSC code.
Choose one of these CSC codes:
BST Boost
VZW Verizon
ATT ATT
USC US Cellular
ACG C Spire
TMK MetroPCS
VMU Virgin Mobile
TFN Tracfone
XAS Sprint
TMB T-Mobile
XAA Unlocked US
SPR Sprint
CCT Xfinity Mobile
AIO Cricket
36) Type in "exit" in the ADB shell.
37) Type in "adb reboot bootloader" and flash your desired firmware by following the "Flashing Standard Firmware" section of this guide or by following the "Flashing Unlocked Firmware" section of this guide. PROFIT FOR NOW.

Flashing Unlocked Firmware:
NOTE: The unlocked firmware does NOT unlock your phone for use on other carriers, it only removes bloatware. Some carrier specific features, such as Wi-Fi Calling and VOLTE will not work with the Unlocked Firmware.
Prerequisites: What's listed in the "Prerequisites for anything you decide to do in this guide" section
Prince Comsy version of Odin
Unlocked Firmware (either Bootloader v1 or Bootloader v2)
Steps:
1) Extract the Prince Comsy version of Odin and the Unlocked Firmware you downloaded from below.
2) Turn off your S8+.
3) Once off, hold the Power button, Volume Down button, and the Bixby button until you see a blue screen on your phone.
4) Press the Volume Up key to enter Download Mode.
5) On your PC, navigate to your extracted Prince Comsy Odin folder.
6) Double click on the "Odin PrinceComsy" executable (Odin PrinceComsy.exe).
7) Connect your phone to your PC with your USB cable.
8) You should see PrinceComsy's Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
9) Now it's time to add your firmware files that were extracted earlier. Individually add an appropriate firmware file for each box on the right. The "BL" box will require a firmware file that starts with "BL", the "AP" box will require a firmware file that starts with "AP", the "CP" box will require a firmware file that starts with "CP", and the "CSC" box will require a firmware file that starts with "CSC" (DO NOT USE THE "HOME_CSC" file for the "CSC" box).
10) Go to the "Options" tab and make sure that only the "Auto Reboot" and "F. Reset Time" checkboxes are ticked.
11) Go back to the "Log" tab.
12) Click the "Start" button on bottom right.
13) Sit back and relax for a while. Odin will output what is being flashed in the "Log" and on a box in the top left.
14) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
15) Once the flash finished, disconnect your phone from your computer.
16) Your phone will do an erase at this point, so don't mess with your phone until you reach the setup screen.
17) Continue with the setup on your phone and enjoy!

A HUGE thanks goes to @STF_TimelessGoD @mweinbach @MJHawaii and @juvemex for their original guides that I based this guide around.
DOWNLOADS:
Standard Odin: https://xdaforums.com/showpost.php?p=75703449&postcount=276
Prince Comsy's Odin: https://www.androidfilehost.com/?fid=24591023225177749
Samsung Drivers: http://developer.samsung.com/galaxy/others/android-usb-driver-for-windows
Canadian HOME_CSC (Bootloader v1): https://androidfilehost.com/?fid=817906626617958535
Canadian HOME_CSC (Bootloader v2): https://androidfilehost.com/?fid=746010030569947264
Factory Binary (Bootloader v1): https://androidfilehost.com/?fid=745425885120731328
Factory Binary (Bootloader v2): https://androidfilehost.com/?fid=673791459329065785 Thank you, @BlueFox721 for letting me provide this.
Google Platform-Tools (ADB):https://dl.google.com/android/repository/platform-tools-latest-windows.zip
Unlocked Firmware (Bootloader v1): (Will be uploaded shortly)
Unlocked Firmware (Bootloader v2): Use SamFirm.
AT&T S8+ Firmware (Bootloader v1): https://androidfilehost.com/?fid=746010030569947263
AT&T S8+ Firmware (Bootloader v2): Missing (Not even available by using SamFirm due to tight AT&T security) :(
 
Last edited:
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leyvatron

leyvatron

Senior Member
Dec 6, 2007
3,024
399
Los Angeles
you should do a pro and con section.

I have seen a few threads regarding this matter, but what are the benefits of this, and why would anyone want to switch.
 
M

Mike15678

Senior Member
Jun 18, 2017
253
192
leyvatron said:
I guess what I am trying to say is, a brief explanation to both would be a good addition to the thread.

Pros and Cons.
Why would I want to odin an unlocked FW oppose to keeping my Verizon FW besides removing a few bloat?
Click to expand...
Click to collapse

Ok, I will shout you out (if that's fine with you) and give some pros and cons on both guides regarding carrier switching and flashing unlocked firmware, by tomorrow. Thanks for your suggestion!
 
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leyvatron

leyvatron

Senior Member
Dec 6, 2007
3,024
399
Los Angeles
Mike15678 said:
Ok, I will shout you out (if that's fine with you) and give some pros and cons on both guides regarding carrier switching and flashing unlocked firmware, by tomorrow. Thanks for your suggestion!
Click to expand...
Click to collapse

Truthfully, I don't need a shout out or anything. I just know noobs are ready to flash anything and everything with the word unlocked without knowing what it is or what it does.

Pros and cons would be a good addition but will require more research time and feedback from people who are using the unlocked FW.
 
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M

Mike15678

Senior Member
Jun 18, 2017
253
192
leyvatron said:
Truthfully, I don't need a shout out or anything. I just know noobs are ready to flash anything and everything with the word unlocked without knowing what it is or what it does.

Pros and cons would be a good addition but will require more research time and feedback from people who are using the unlocked FW.
Click to expand...
Click to collapse

I'll still shout you out (at the top of my guide)... I do have an S8, and can tell you that VOLTE and Wi-Fi Calling are not in the settings with the Verizon firmware or with the unlocked firmware by itself (meaning that the SIM card was removed and the CSC was set to "XAA"). Therefore, that has led me to believe that Samsung themselves, have not implemented any carrier exclusive features, such as the ones stated above. I also collected some input from the users at the S8 guide, and they report the same things.
 
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Mike15678

Senior Member
Jun 18, 2017
253
192
Oh, I want to point out that there IS a stock AT&T firmware for the S8+.
On the S8, there isn't.
(Just updated the guide)
 
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AxlxA

Senior Member
Jun 17, 2013
136
29
Thanks, would like to know if this will work with an 955U trying to get AT&T wifi calling/volte to work by going to ATT firmware?
 
M

Mike15678

Senior Member
Jun 18, 2017
253
192
AxlxA said:
The Unlocked firmware. It's a samsung.com Galaxy S8+ purchased as an unlocked device. What do you mean by standard firmware? like with the carriers?
Click to expand...
Click to collapse

Yes, that's what I mean by standard firmware (sorry, if I confused you). Your CSC code is already set to "ATT", correct? If not, follow the "Carrier Switching" section and then the "Flashing Standard Firmware" section. If your CSC code is alrready set to "ATT", then just proceed with the "Flashing Standard Firmware" section.
 
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    Mike15678
    Hello, there. This is my second guide, so please forgive me if it looks a bit weird. But without further ado I present you with my Official [Snapdragon] Guide for Flashing Standard Firmware, Carrier Switching, and Flashing Unlocked Firmware for the S8+.[/SIZE]
    Here are some useful reminders:
    All download links are at the bottom of this post.
    Make sure you follow the "Prerequisites For Anything You decide To Do In This Guide" section.
    Don't copy quotation marks, unless I tell you to in this guide.
    You will need a Windows computer in order to utilize the software provided. Mac users can use Boot Camp to dual boot their machines. Using WINE is not recommended.
    This is an S8+ guide, not an S8 guide. Go to https://xdaforums.com/galaxy-s8/how-to/snap-guide-flashing-standard-fw-carrier-t3625817 to check out my S8 guide.
    WARNING: Anything you do in this guide will erase your phone completely. It's recommended that you back up before you do anything and that you remove your Google account from your phone (so you don't have to go through FRP).
    Note: Flashing to stock from Unlocked firmware requires you to follow the "Carrier Switching" section (which eventually requires you to follow the "Flashing Standard Firmware" section) and do as it says, unless the CSC code of your carrier is currently active. You can check this by going into Recovery Mode by holding the Power button, Bixby button, and Volume Up button until you see a dark blue screen with text saying that the firmware is being updated (it's not actually). Once it transitions to a black screen, your active CSC will be on the bottom log (three characters). If your CSC code is already your carrier's, then just follow the "Flashing Standard Firmware section. But for anything you decide to do, you must follow the "Prerequisites for anything you decide to do in this guide" section.

    Disclaimer:
    I am NOT responsible for any damage done to your device if you decide to use this guide.

    Prerequisites for anything you decide to do in this guide (Required):

    Standard Odin
    Samsung Drivers
    Steps:
    1) Uninstall Samsung Switch and/or Samsung Kies, if present on your computer. This helps removes any conflicts with Odin.
    2) Extract the Samsung Driver zip and the Odin zip to somewhere safe on your computer.
    3) Double click on the extracted "SAMSUNG_USB_Driver_for_Mobile_Phones" executable (SAMSUNG_USB_Driver_for_Mobile_Phones.exe).
    3) Navigate to your extracted Odin folder and double click on the Odin configuration file (Odin3.ini).
    4) You should have entered Notepad (or your preferred note editor). Find the "[ButtonOption]" section.
    5) There should be a setting there called "UMS/PATCH". Change the value of "0" to "1" so it becomes "UMS/PATCH=1".
    6) Press the "Ctrl" key and "S" key on your keyboard to save the file.
    7) Go ahead and close out of Notepad.


    All About Bootloaders (Required Reading):
    As Wikipedia puts it, “A boot loader is a computer program that loads an operating system or some other system software for the computer after completion of the power-on self-tests.” In other words, a bootloader is what loads you operating system. In most Samsung phones (including the S8 and S8+), there’s an e-fuse that prevents downgrading of the bootloader. This means any firmware or firmware update containing a lower Bootloader version than the one you have, will FAIL to be applied. There is really no way to circumvent this.
    (From what I can tell) S8+ firmware released since December are Bootloader v2, while anything before that month is Bootloader v1. In the next section, I’ll be explaining how to properly identify your current Bootloader version.

    How to identify Bootloader version (Important):
    Steps:
    1) Open “Settings” on your phone.
    2) Scroll down to “About Phone”.
    3a) If you are on a standard, carrier firmware, under “Baseband version” you should see something similar to this: “G955UXXXXXXXX”.
    3b) If you are on an unlocked firmware, under “Baseband version” you should see something similar to this: “G955U1XXXXXXXX”.
    4) No matter which firmware you're on, the fourth “X” would be either a “1” or a “2”, which means you will have either Bootloader version 1 or Bootloader version 2, respectively.

    Note: As stated in the last section attempting to flash firmware that contains Bootloader v1 onto a phone that already has Bootloader v2, will fail. You can update a phone on Bootloader v1 to a firmware that has Bootloader v2, however.
    How To Download Firmware with Updato:
    Note: This is an add-on section for any part of the guide that requires you to download specific firmware.
    Updato can download old or new firmware for phones, therefore you can download Bootloader v1 or Bootloader v2 firmware. However, Updato tends to be much slower than SamFirm, therefore its recommended that you use SamFirm if you’re willing to download Bootloader v2 firmware. You should only use Updato if you need to download Bootloader v1 firmware.
    Steps:
    1) Go to http://fw.updato.com
    2) Type in your Model Number (SM-G955U for carrier S8+’s; Firmware for unlocked S8+’s can be found in the “Downloads” section)
    3) Find firmware for your specific region.
    Here are some common Region codes:
    BST Boost
    VZW Verizon
    ATT ATT
    USC US Cellular
    ACG C Spire
    TMK MetroPCS
    VMU Virgin Mobile
    TFN Tracfone
    XAS Sprint
    TMB T-Mobile
    XAA Unlocked US
    SPR Sprint
    CCT Xfinity Mobile
    AIO Cricket

    4) Download it somewhere safe onto your computer.

    How To Download Firmware with SamFirm (Faster):
    Note: This is an add-on section for any part of the guide that requires you to download specific firmware.
    SamFirm can only download the latest firmware for phones, therefore you’ll be downloading a Bootloader v2 firmware (which means once you flash it, there's no going back to Bootloader v1 if your phone is currently on that version). SamFirm tends to be much faster than Updato for downloading firmware, since the firmware is downloaded directly from Samsung.
    Prerequisites:
    SamFirm (SamFirm_v0.3.6.zip):https://xdaforums.com/galaxy-tab-s/general/tool-samfirm-samsung-firmware-t2988647
    Steps:
    1) Download “SamFirm_v0.3.6.zip”. Make sure you’ve installed all of its prerequisites listed on the page, such as “.NET Framework 3.5”, “Microsoft Visual C++ 2008 Redistributable Package (x86)”, and “Microsoft Visual C++ 2010 Redistributable Package (x86)”
    2) Extract “SamFirm_v0.3.6.zip” somewhere safe onto your computer.
    3) Double-click on “SamFirm.exe” to open it.
    4) Enter your Model Number and 3-character Region code.
    Here are some common Region codes:
    BST Boost
    VZW Verizon
    ATT ATT
    USC US Cellular
    ACG C Spire
    TMK MetroPCS
    VMU Virgin Mobile
    TFN Tracfone
    XAS Sprint
    TMB T-Mobile
    XAA Unlocked US
    SPR Sprint
    CCT Xfinity Mobile
    AIO Cricket

    5) Make sure you’ve ticked the “Manual” checkbox.
    6) Input your “PDA”, “CSC”, and “Phone” strings into their respective slots based off the information found from fw.updato.com for your latest specific firmware. Please note that the “CSC” slot is not the same as the same as the “Region” slot; the “CSC” slot should have a long string inputted.
    7) Tick the “Binary Nature” checkbox.
    8) Click the “Check Update” box.
    9) Your firmware should now appear. Make sure the “Check CRC32” and “Decrypt Automatically” checkboxes are ticked.
    10) Click on the “Download” box, choose where you want to store the firmware, and relax for a while.

    Flashing Standard Firmware:
    Prerequisites:
    What's listed in the "Prerequisites For Anything You Decide To Do In This Guide" section.
    Firmware you want to flash; follow the “How To Download Firmware with SamFirm” or “How To Download Firmware with Updato” section, if you need firmware.
    Steps:
    1) Extract your downloaded firmware to somewhere safe on your computer.
    2) Turn off your S8+.
    3) Once off, hold the Power button, Volume Down button, and the Bixby button until you see a blue screen on your phone.
    4) Press the Volume Up key to enter Download Mode.
    5) On your computer, navigate to your extracted Odin folder.
    6) Double click on the "Odin3 v3.12.7" executable (Odin3 v3.12.7.exe)
    7) Connect your phone to your computer with your USB cable.
    8) You should see Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
    9) Now it's time to add your firmware files that were extracted earlier. Individually add an appropriate firmware file for each box on the right. The "BL" box will require a firmware file that starts with "BL", the "AP" box will require a firmware file that starts with "AP", the "CP" box will require a firmware file that starts with "CP", the "CSC" box will require a firmware file that starts with "CSC" (DO NOT USE THE "HOME_CSC" file for the "CSC" box), the "UMS" box will require a firmware file that starts with "USERDATA". The "AP" and "USERDATA" files will take the longest for Odin to load because of their size.
    10) Go to the "Options" tab and make sure that only the "Auto Reboot" and "F. Reset Time" checkboxes are ticked.
    11) Go back to the "Log" tab.
    12) Click the "Start" button on bottom right.
    13) Sit back and relax for a while. Odin will output what is being flashed in the "Log" and on a box in the top left.
    14) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
    15) Once the flash finished, disconnect your phone from your computer.
    16) Your phone will do an erase at this point, so don't mess with your phone until you reach the setup screen.
    17) PROFIT. Follow the setup on your phone and you're good to go.

    Carrier Switching:
    NOTE: Doing this process does NOT unlock your phone for use on other carriers.
    Prerequisites:
    What's listed in the "Prerequisites for anything you decide to do in this guide" section.
    S8+ Factory Binary (either Bootloader v1 or Bootloader v2)
    Prince Comsy version of Odin
    Google Platform-Tools (ADB)
    Canadian HOME_CSC (either Bootloader v1 or Bootloader v2)
    Steps:
    1) Extract the downloaded S8+ Factory Binary, the Prince Comsy version of Odin, Platform-Tools, and the Canadian firmware, to somewhere safe on your computer.
    2) Turn off your S8+.
    3) Once off, hold the Power button, Volume Down button, and the Bixby button until you see a blue screen on your phone.
    4) Press the Volume Up key to enter Download Mode.
    5) Navigate to the extracted Odin (NOT PRINCE COMSY) folder.
    6) Double click on the "Odin3 v3.12.7" executable (Odin3 v3.12.7.exe).
    7) Connect your phone to your computer with your USB cable.
    8) You should see Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
    9) Click on the "AP" box and navigate to the extracted Factory Binary folder. Double click on the file the starts with "COMBINATION".
    10) Wait for Odin to load the file.
    11) Go to the "Options" tab and make sure that only "Auto Reboot" and "F. Reset Time" checkboxes are ticked.
    12) Go back to the "Log" tab.
    13) Click the "Start" button on bottom right.
    14) Odin will output what is being flashed in the "Log" and on a box in the top left.
    15) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
    16) Leave your phone connected and let your it reboot into the 'factory binary homescreen' (Basically, the equivalent of a home screen on a regular S8+).
    17) Navigate to the "platform-tools-latest-windows" folder. Once you’ve navigated to where “adb.exe” is located, click the address bar on the top and press “Ctr+C”.
    18) Open cmd.exe through “Run” (Windows key + R)
    19) Type in “cd /d “<copied folder location>”” (Make sure you’re putting the folder location in quotes and not the command itself)
    20) Type in "adb reboot bootloader". Leave ADB open.
    21) Your phone will reboot into Download Mode. Your device should still be connected and ADB should also still be open.
    22) Navigate to the Prince Comsy version of Odin and double click on the "Odin PrinceComsy" executable (Odin PrinceComsy.exe).
    23) You should see the Prince Comsy version of Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
    24) Click the "CSC" box and navigate to the “HOME_CSC” file you downloaded.
    25) Double click on the file that starts with "HOME_CSC" (DO NOT USE the "CSC" file for the "CSC" box). It should load quickly.
    26) Go to the "Options" tab and make sure that only "Auto Reboot" and "F. Reset Time" are ticked.
    27) Go back to the "Log" tab.
    28) Click the "Start" button on bottom right.
    29) Odin will output what is being flashed in the "Log" and on a box in the top left.
    30) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
    31) Once your phone reboots, you will see an "IME" button on the 'factory binary homescreen (It’s on the bottom). Tap on it.
    32) A number pad should appear. Type in "*#243203855#".
    33) A menu will pop up. Scroll down until you find an "XAC" option. Tap on it and tap "Install".
    34) Your phone will reboot. Once it reaches the 'factory binary homescreen', go to ADB on your computer and type in "adb shell".
    35) *LOOK A TINY BIT BELOW!* Type in "echo "XXX" > /efs/imei/mps_code.dat" (the quotation marks that surround the X's are used, but not the ones that surround the whole command... you know that by now- right?) and REPLACE XXX with your preferred CSC code.
    Choose one of these CSC codes:
    BST Boost
    VZW Verizon
    ATT ATT
    USC US Cellular
    ACG C Spire
    TMK MetroPCS
    VMU Virgin Mobile
    TFN Tracfone
    XAS Sprint
    TMB T-Mobile
    XAA Unlocked US
    SPR Sprint
    CCT Xfinity Mobile
    AIO Cricket
    36) Type in "exit" in the ADB shell.
    37) Type in "adb reboot bootloader" and flash your desired firmware by following the "Flashing Standard Firmware" section of this guide or by following the "Flashing Unlocked Firmware" section of this guide. PROFIT FOR NOW.

    Flashing Unlocked Firmware:
    NOTE: The unlocked firmware does NOT unlock your phone for use on other carriers, it only removes bloatware. Some carrier specific features, such as Wi-Fi Calling and VOLTE will not work with the Unlocked Firmware.
    Prerequisites: What's listed in the "Prerequisites for anything you decide to do in this guide" section
    Prince Comsy version of Odin
    Unlocked Firmware (either Bootloader v1 or Bootloader v2)
    Steps:
    1) Extract the Prince Comsy version of Odin and the Unlocked Firmware you downloaded from below.
    2) Turn off your S8+.
    3) Once off, hold the Power button, Volume Down button, and the Bixby button until you see a blue screen on your phone.
    4) Press the Volume Up key to enter Download Mode.
    5) On your PC, navigate to your extracted Prince Comsy Odin folder.
    6) Double click on the "Odin PrinceComsy" executable (Odin PrinceComsy.exe).
    7) Connect your phone to your PC with your USB cable.
    8) You should see PrinceComsy's Odin output "Added!!" in the "Log" tab and underneath the "ID:COM" section, you should see an empty box turn blue.
    9) Now it's time to add your firmware files that were extracted earlier. Individually add an appropriate firmware file for each box on the right. The "BL" box will require a firmware file that starts with "BL", the "AP" box will require a firmware file that starts with "AP", the "CP" box will require a firmware file that starts with "CP", and the "CSC" box will require a firmware file that starts with "CSC" (DO NOT USE THE "HOME_CSC" file for the "CSC" box).
    10) Go to the "Options" tab and make sure that only the "Auto Reboot" and "F. Reset Time" checkboxes are ticked.
    11) Go back to the "Log" tab.
    12) Click the "Start" button on bottom right.
    13) Sit back and relax for a while. Odin will output what is being flashed in the "Log" and on a box in the top left.
    14) The box in the top left will become green and in black letters say "PASS" once the flash was successful.
    15) Once the flash finished, disconnect your phone from your computer.
    16) Your phone will do an erase at this point, so don't mess with your phone until you reach the setup screen.
    17) Continue with the setup on your phone and enjoy!

    A HUGE thanks goes to @STF_TimelessGoD @mweinbach @MJHawaii and @juvemex for their original guides that I based this guide around.
    DOWNLOADS:
    Standard Odin: https://xdaforums.com/showpost.php?p=75703449&postcount=276
    Prince Comsy's Odin: https://www.androidfilehost.com/?fid=24591023225177749
    Samsung Drivers: http://developer.samsung.com/galaxy/others/android-usb-driver-for-windows
    Canadian HOME_CSC (Bootloader v1): https://androidfilehost.com/?fid=817906626617958535
    Canadian HOME_CSC (Bootloader v2): https://androidfilehost.com/?fid=746010030569947264
    Factory Binary (Bootloader v1): https://androidfilehost.com/?fid=745425885120731328
    Factory Binary (Bootloader v2): https://androidfilehost.com/?fid=673791459329065785 Thank you, @BlueFox721 for letting me provide this.
    Google Platform-Tools (ADB):https://dl.google.com/android/repository/platform-tools-latest-windows.zip
    Unlocked Firmware (Bootloader v1): (Will be uploaded shortly)
    Unlocked Firmware (Bootloader v2): Use SamFirm.
    AT&T S8+ Firmware (Bootloader v1): https://androidfilehost.com/?fid=746010030569947263
    AT&T S8+ Firmware (Bootloader v2): Missing (Not even available by using SamFirm due to tight AT&T security) :(
    View
    3
    J
    jlord
    skoalbandit1 said:
    All of the ATT firmware i try to download does not have the userdata file. My unlocked phone currently has a CSC code : ATT. Can i just flash without the userdata? I am looking to activate the wifi calling feature on this phone.
    Click to expand...
    Click to collapse

    Make sure you are downloading SM-G955U and not SM-G955U1 version.
    View
    3
    M
    Mike15678
    AxlxA said:
    That makes sense. Too bad I can't find the SM-G955A firmware. not even on sammobile.
    Click to expand...
    Click to collapse

    The model number for the firmware is "SM-G955U". The CSC is "ATT". Here's a link to the firmware: http://updato.com/firmware-archive-select-model?record=EF1356CA26EE11E7963AFA163EE8F90B.
    View
    3
    leyvatron
    leyvatron
    Mike15678 said:
    Ok, I will shout you out (if that's fine with you) and give some pros and cons on both guides regarding carrier switching and flashing unlocked firmware, by tomorrow. Thanks for your suggestion!
    Click to expand...
    Click to collapse

    Truthfully, I don't need a shout out or anything. I just know noobs are ready to flash anything and everything with the word unlocked without knowing what it is or what it does.

    Pros and cons would be a good addition but will require more research time and feedback from people who are using the unlocked FW.
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    3
    M
    Mike15678
    roc342 said:
    Im on sprint, And all I want is the Unlocked Firmware without any sprint bloat. Do I need to Change my CSC from SPR to XAA first. Or Can I just Flash the unlocked firmware? If i leave the CSC will it download some of the bloat via OTA. Like the stock sprint firmware? Aplogies I know the answer is here but Having trouble finding it.
    Click to expand...
    Click to collapse

    Sorry about the extremely late response, but you can just flash the unlocked firmware by following the appropriate section of the guide. Changing your CSC to "XAA" would allow your phone to accept any supported U.S. SIM card and automatically change the CSC to that carrier. In your case, you don't have to do this.
    Once you have unlocked firmware, you receive OTA updates directly from Samsung and get no bloatware from your carrier.
    View

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