Database Users

N910C EFS partition is ?corrupted? Not a single ROM boots. In dire need of help.

Everything was fine until I flashed CM13 unofficial.
Now, my bootloader is updated to 6.0 (COJ5 something or COH4), I can't revert to something prior to that: odin fails at sboot.bin NAND write start fail.
-While this issue has occured to many others than me, I'm the only one who can't even boot into CM13 or AOSP based ROMs, even after pushing different variants of ROMs several times through ADB, bootloops are still persistent.
-Any other 5.1.1 Official ROM that's not COJ5 or COH4 fails to flash at odin. COJ5/COH4 ROMS flash succesfully, but the phone doesn't boot past the samsung text.
-I have tried flashing various COH4 ROMS along with their AP,BL,CSC etc, everything flashes succesfully apart from the bootloader file, and after that it's the same samsung text brick. I couldn't find the PIT files (bootloader csc n such) for COJ5..
Is there a place I can find a backed up EFS partion ?file? and restore it myself? Would this get me out of the****hole i'm currently in?
What can I do about this...

Nortabun said:
Everything was fine until I flashed CM13 unofficial.
Now, my bootloader is updated to 6.0 (COJ5 something or COH4), I can't revert to something prior to that: odin fails at sboot.bin NAND write start fail.
-While this issue has occured to many others than me, I'm the only one who can't even boot into CM13 or AOSP based ROMs, even after pushing different variants of ROMs several times through ADB, bootloops are still persistent.
-Any other 5.1.1 Official ROM that's not COJ5 or COH4 fails to flash at odin. COJ5/COH4 ROMS flash succesfully, but the phone doesn't boot past the samsung text.
-I have tried flashing various COH4 ROMS along with their AP,BL,CSC etc, everything flashes succesfully apart from the bootloader file, and after that it's the same samsung text brick. I couldn't find the PIT files (bootloader csc n such) for COJ5..
Is there a place I can find a backed up EFS partion ?file? and restore it myself? Would this get me out of the****hole i'm currently in?
What can I do about this...
Click to expand...
Click to collapse
Hi, this may help you http://forum.xda-developers.com/note-4/help/fix-note4-exynos-n910c-bootloop-problem-t3312161

mangui said:
Hi, this may help you http://forum.xda-developers.com/note-4/help/fix-note4-exynos-n910c-bootloop-problem-t3312161
Click to expand...
Click to collapse
Yea i came across this, but there was one tiny problem
how on earth am i supposed to root, get busybox, and apply usb debugging on my phone while it has no functional ROM?
and how on earth am i supposed to transfer a backup from my ROMless phone?

Do you have a pit file for repartition
If so, access twrp , wipe everything including your internal storage. Then boot into download mode.
In the computer, load the pit file and your stock coj5 into Odin 3.10 , tick "repartition" and "Nand Erase All"then click start.
Back to your phone - which now should be boot looping - access the stock recovery and wipe. Root - try using a different root method like chainfire's Odin autoroot - then twrp ur phone. Flash cm13 then start running the steps I threaded ( [fix] note 4 exynos bootloop problem ...... )
PM me for what you get
Sent from my HTC Desire 820s dual sim using Tapatalk

TWRP not working with bph6

I just upgraded to the latest G935FXXU1BPH6 using Odin (v3.12.3). With past firmware releases, I was able to load TWRP twrp-3.0.2-2-hero2lte.img.tar using Odin and then proceed to root the phone.
However, with BPH6, TWRP refuses to boot. I try the volume-up+home+power sequence but TWRP recovery never starts. The phone just sits there on the boot screen.
I'm able to recover by re-flashing the BPH6 firmware but this leaves me thinking that the bootloader has changed in BPH6 and twrp 3.0.2-2 is no longer compatible.
1) Anyone else having this issue?
2) Any solutions or workarounds?
3) Do people think it would be safe to dowgrade the bootloader or entire firmware? I'm willing to try it but I'm a little concerned about bricking the phone.

kociubin said:
I just upgraded to the latest G935FXXU1BPH6 using Odin (v3.12.3). With past firmware releases, I was able to load TWRP twrp-3.0.2-2-hero2lte.img.tar using Odin and then proceed to root the phone.
However, with BPH6, TWRP refuses to boot. I try the volume-up+home+power sequence but TWRP recovery never starts. The phone just sits there on the boot screen.
I'm able to recover by re-flashing the BPH6 firmware but this leaves me thinking that the bootloader has changed in BPH6 and twrp 3.0.2-2 is no longer compatible.
1) Anyone else having this issue?
2) Any solutions or workarounds?
3) Do people think it would be safe to dowgrade the bootloader or entire firmware? I'm willing to try it but I'm a little concerned about bricking the phone.
Click to expand...
Click to collapse
In Odin flash an older firmware then reroot and wait for a root update from Chainfire and the TWRP team
I know a couple people that have done that.
"And on that bombshell!"
Sent from my Echoe powered AEL Driven G935F

When I first upgraded to the new firmware, I found the same thing that you did - I wanted to be able to flash custom roms and didn't know when or if TWRP and ROOT was going to be possible with this new firmware - so I used odin and reflashed July's Firmware and I was able to do so without any Issues - so then I decided to try to upgrade the AP/CSC/CP files from the latest update and replaced the bootloader with the bootloader from july's update and it worked.
Good luck - frankly I am Concerned. It appears that the latest bootloader from Samsung is LOCKED - I only hope someone is able to get root and twrp working - and I hope this is not an indication of future issues for rooting samsung phones....

mocsab said:
Good luck - frankly I am Concerned. It appears that the latest bootloader from Samsung is LOCKED - I only hope someone is able to get root and twrp working - and I hope this is not indication of future issues for rooting samsung phones....
Click to expand...
Click to collapse
No it isn't. Korean models had already been incompatible with official TWRP since firmware APG7 and I confirmed it working again when I replaced the kernel inside TWRP with one built from the latest source released by Samsung. So, someone needs to build a new TWRP recovery with BPH6 kernel source and everything will become fine again.

I didnt know that but it is very good news as far as I am concerned.
I have alwasy been fearful that Samsung was going to eventually lock down their international phones like they did to the US Variants - and when this originally happened to me, I started thinking that maybe my worst fears had come true. Thanks for the information....

I have the same question，but i soved it，i Flash the old BL and TWRP can working
BL version ：BL_G935FXXU1APGH_CL8252943_QB10274482_REV00_user

Xlim said:
I have the same question，but i soved it，i Flash the old BL and TWRP can working
BL version ：BL_G935FXXU1APGH_CL8252943_QB10274482_REV00_user
Click to expand...
Click to collapse
pls send related boot loader download link

same iussue .. some news??
by the way to use root now i put the old firmwere

FARSHOOD said:
pls send related boot loader download link
Click to expand...
Click to collapse
https://www.androidfilehost.com/?fid=24671318762848807

When flashing bootloader in Odin there is an options tab, there are checkboxes - Auto Reboot which is checked - Re-Partiion which is unchecked - and - F.Reset Time which is checked, I flashed new bootlaoder and modem and now my phone will not restart no matter the key combination I press. So Are those checkboxes suppose to be checked off or unchecked

SM-A310F Downgrade from 6.0.1 to 5.1.1

Hi XDA community, i want try to downgrade in my A310f from Android 6.0.1 to 5.1.1. It's possible? I try to download the 5.1.1 from Sammobile, but when i flash the firmware with odin i get the error "SW Rev Check Fail" in my phone and "md5 error" from odin.. there are some method?

MMBB29K.A310FXXU3BQC2 is my model. Tell me please here

allenbtc said:
MMBB29K.A310FXXU3BQC2 is my model. Tell me please here
Click to expand...
Click to collapse
If your bootloader also is upgraded to A310FXXU3 then it won't be possible to downgrade to 5.1.1 through odin.
Maybe with a modified package without cm.bin, modem.bin, sboot.bin. Otherwise, make it flashable and use twrp.
With Odin you'll only be able to downgrade to the latest 6.0.1 which is also A310FXXU3.

how i can flash with twrp?
---------- Post added at 02:02 PM ---------- Previous post was at 01:57 PM ----------
tys0n said:
If your bootloader also is upgraded to A310FXXU3 then it won't be possible to downgrade to 5.1.1 through odin.
Maybe with a modified package without cm.bin, modem.bin, sboot.bin. Otherwise, make it flashable and use twrp.
With Odin you'll only be able to downgrade to the latest 6.0.1 which is also A310FXXU3.
Click to expand...
Click to collapse
how i can flash with twrp?

tys0n said:
If your bootloader also is upgraded to A310FXXU3 then it won't be possible to downgrade to 5.1.1 through odin.
Maybe with a modified package without cm.bin, modem.bin, sboot.bin. Otherwise, make it flashable and use twrp.
With Odin you'll only be able to downgrade to the latest 6.0.1 which is also A310FXXU3.
Click to expand...
Click to collapse
I can confirm this method is working, I have successfully downgraded an A3 2016 from A310FXXU3BQD2 to A310FXXU2BQA3.
I used the Tar tool from this thread with all the files from the update I wanted to downgrade to, except sboot.bin, cm.bin and modem.bin. It's very important to NOT copy those files to the tool folder because otherwise your phone will be laggy and SIM unusable (if you use the old modem) or you will not be able to flash like with the original tar (if you use old sboot or cm).
So after I ran the batch file, I did a wipe data/factory reset using original recovery and then I flashed the "all files" tar the tool created using Odin in AP (only Auto Reboot and F. reset time checked) and the phone in download mode, and It worked like a charm.
With this method you can likely have any old update flashed while keeping the latest secure bootloader, cm and modem. (Notice that after the downgrade, the phone cannot find any new updates, maybe it's related to the bootloader being the latest or the fact I only downgraded to the previous update...)

dealth645 said:
I can confirm this method is working, I have successfully downgraded an A3 2016 from A310FXXU3BQD2 to A310FXXU2BQA3.
I used the Tar tool from this thread with all the files from the update I wanted to downgrade to, except sboot.bin, cm.bin and modem.bin. It's very important to NOT copy those files to the tool folder because otherwise your phone will be laggy and SIM unusable (if you use the old modem) or you will not be able to flash like with the original tar (if you use old sboot or cm).
So after I ran the batch file, I did a wipe data/factory reset using original recovery and then I flashed the "all files" tar the tool created using Odin in AP (only Auto Reboot and F. reset time checked) and the phone in download mode, and It worked like a charm.
With this method you can likely have any old update flashed while keeping the latest secure bootloader, cm and modem. (Notice that after the downgrade, the phone cannot find any new updates, maybe it's related to the bootloader being the latest or the fact I only downgraded to the previous update...)
Click to expand...
Click to collapse
Thanks for confirming. I've never tried it myself but I figured those bins are the U1/U2/U3 binary files that are protected for downgrade, so it should probably work without them
Now we know how to easily downgrade without errors.

Downgrade
Hello,
With my sm-a310f I downgraded from Nougat to Marchmallow but could not get back to Lollipop.
I used TWRP and Odin.
I saw that there were solutions but they are not universal. Can someone point me?
Thank you

menuisier3 said:
Hello,
With my sm-a310f I downgraded from Nougat to Marchmallow but could not get back to Lollipop.
I used TWRP and Odin.
I saw that there were solutions but they are not universal. Can someone point me?
Thank you
Click to expand...
Click to collapse
https://forum.xda-developers.com/samsung-a-series/general/rom-t3614602

flash combination rom before flash full 4 file stock rom 5.1 , u can downgrade your phone.

Tanle11 said:
flash combination rom before flash full 4 file stock rom 5.1 , u can downgrade your phone.
Click to expand...
Click to collapse
No! You can't downgrade bootloader even if you use a 4 file repair firmware.

As far as I am aware of, this is the only possible way to downgrade to 5.1.1 if you are on new bootloader/modem (tested by me - works fine, I am on the newer bootloader/modem combo) :
https://forum.xda-developers.com/samsung-a-series/general/rom-t3614602
(consider this however ONLY if you are willing to trade 5.1.1 for the warranty as you would need to flash TWRP in the process first)

G935A to G935U (Accidentally wiped Stock ROM. Stuck in Recovery + Download)

I recently picked up 2 edges a Verizon and ATT variant, I flashed the Verizon phone succesfully to G935U with this firmware http://i.imgur.com/JuIeA6g.jpg
(The 4-file link in Step 2 https://forum.xda-developers.com/ve...de-flashing-sm-935u-firmware-verizon-t3415145 )
Since that went smoothly I decided to run Odin and flash that firmware onto the ATT Edge, ( original FW is g935aucs4apk1 )
It didn't work, I recall that it got stuck at Setup Connection. So I rebooted the phone and it took me into Recovery mode, where all the CHECKS failed. So the ROM has effectively been wiped; leaving me with just the Recovery menu and DOWNLOAD screens.
Is there any way of getting my self out of this?

Fixed it. Ended up clicking Re-partition and Flash Bootloader in Odin then flashing 4-files from the T-Mobile Nougat firmware using the PrinceComsy 3.12 Odin
Not my ideal way to do this, i'm sure I've lost root potential, but I have a working phone! (w/ No xposed )

borealis17 said:
Fixed it. Ended up clicking Re-partition and Flash Bootloader in Odin then flashing 4-files from the T-Mobile Nougat firmware using the PrinceComsy 3.12 Odin
Not my ideal way to do this, i'm sure I've lost root potential, but I have a working phone! (w/ No xposed )
Click to expand...
Click to collapse
As long as you are still on bootloader 4 (and you are, since to my knowledge there isn't a higher version) you can still root your device and return it to MM if necessary. It may take some effort, but it's doable.

Can I downgrade the Samsung Bootloader from SW Rev 3 to 2?

Hi,
I want to downgrade my SM-A310F to earlier Android versions, but Odin blocks this with the Error: "SW REV. CHECK FAIL. DEVICE: 3. BINARY: 2."
So apparently I can only install firmware files which come with the same Bootloader I'm currently on (so 3) and not earlier versions. For me it's Android 7 and the latest update of 6.0.1 which where made for this bootloader. But I want to downgrade to earlier versions of Android (please don't ask why, I know that these don't have the latest security patches etc. pp.).
So my first idea was I should downgrade the bootloader first so it matches the firmware I want to install. I extracted the recovery.img out of the firmware file, packed it in a .tar file and flashed it successfully through Odin. But unfortunately I get the same error in Odin like above when trying to flash the firmware again, so the bootloader maybe didn't downgrade?!
What can I do to downgrade my bootloader?
I want to install a stock Android ROM, so Custom ROMs are not an option. I heard I can install a Custom Bootloader, like TWRP, which allows installing every firmware?!
But does that trip my KNOX counter? My KNOX is still 0, so if there's an option to downgrade to earlier ROMs without tripping KNOX I'd be glad to hear it.

So I found the answer myself.
Apparently it is not possible to simply downgrade the Bootloader. I didn't fully dig into this, but to simply flash some image with Odin won't do the trick at least.
What works however is to downgrade to an older firmware with an older bootloader even if one keeps the newer bootloader on his device.
So what's the trick? One downloads the firmware file (.tar) which one wants to downgrade to and opens it with an archiver application (7zip). One extracts all the files to a folder and repacks them again in a .tar file but leaving every file out which ends on .bin (e.g. sboot.bin etc.). This .tar file can be flashed like any other firmware file via Odin and it should run through it without any problems.
I can not confirm that the downgrade works for every firmware version, but at least I could downgrade from Android 7 Nougat to 6.0.1 Marshmellow while the first one comes with the SW Rev 3 bootloader and the latter with SW Rev 2 bootloader. Again, I don't know how far into the past this works, e.g. if you can downgrade from 7 to 5.1.1 with this method.
Another option is always a Custom ROM (like this one for 5.1.1 for example) which doesn't check the Bootloader version.
I don't know if this method trips KNOX since I had tripped it already before figuring this out (very well could be, since you're not flashing a signed firmware file anymore...).

mcpossity said:
So I found the answer myself.
Apparently it is not possible to simply downgrade the Bootloader. I didn't fully dig into this, but to simply flash some image with Odin won't do the trick at least.
What works however is to downgrade to an older firmware with an older bootloader even if one keeps the newer bootloader on his device.
So what's the trick? One downloads the firmware file (.tar) which one wants to downgrade to and opens it with an archiver application (7zip). One extracts all the files to a folder and repacks them again in a .tar file but leaving every file out which ends on .bin (e.g. sboot.bin etc.). This .tar file can be flashed like any other firmware file via Odin and it should run through it without any problems.
I can not confirm that the downgrade works for every firmware version, but at least I could downgrade from Android 7 Nougat to 6.0.1 Marshmellow while the first one comes with the SW Rev 3 bootloader and the latter with SW Rev 2 bootloader. Again, I don't know how far into the past this works, e.g. if you can downgrade from 7 to 5.1.1 with this method.
Another option is always a Custom ROM (like this one for 5.1.1 for example) which doesn't check the Bootloader version.
I don't know if this method trips KNOX since I had tripped it already before figuring this out (very well could be, since you're not flashing a signed firmware file anymore...).
Click to expand...
Click to collapse
https://forum.xda-developers.com/samsung-a-series/general/rom-t3614602

So I found the answer myself.
Apparently it is not possible to simply downgrade the Bootloader. I didn't fully dig into this, but to simply flash some image with Odin won't do the trick at least.
What works however is to downgrade to an older firmware with an older bootloader even if one keeps the newer bootloader on his device.
So what's the trick?
mcpossity said:
One downloads the firmware file (.tar) which one wants to downgrade to and opens it with an archiver application (7zip). One extracts all the files to a folder and repacks them again in a .tar file but leaving every file out which ends on .bin (e.g. sboot.bin etc.). This .tar file can be flashed like any other firmware file via Odin and it should run through it without any problems.
Click to expand...
Click to collapse
Hi there mcpossity.
Can you please be more specific on this trick part? Please share the steps you followed.
Regards

With a S7 Edge
Hello,
My phone has updated on the last version of Android 8.0.0 Oreo (01.12.2020), with the last version of Bootloader (7th). I want to downgrade my device to Android 6.0.1, but all version for this OS have BLv1, so I am in the same situation than you (but one gen. later). Can I downgrade my phone, with the same methode ? If so, can you explain this in detail or give me a custom OS ? Thanks in advance.
I tried with this methode and this doesn't work : Odin has shut down when I have started the process. What was wrong ?

Downgrade using old versions of LineageOS?
Hi, I've got the same problem: I installed LineageOS 17.1 (Andoroid 10) which upgraded my Bootloader to 5. Now I need to go back to stock ROM but cannot do so because the error says: "SW REV. CHECK FAIL (BOOTLOADER) DEVICE: 5, BINARY 1.
Is it possible to install an early Lineage OS that downgrades the Bootloader and then install stock ROM? Where would I find the BL version of LineageOS?
Thanks
PS: In my case Galaxy S8

galaxynoobie said:
Hi, I've got the same problem: I installed LineageOS 17.1 (Andoroid 10) which upgraded my Bootloader to 5. Now I need to go back to stock ROM but cannot do so because the error says: "SW REV. CHECK FAIL (BOOTLOADER) DEVICE: 5, BINARY 1.
Is it possible to install an early Lineage OS that downgrades the Bootloader and then install stock ROM? Where would I find the BL version of LineageOS?
Thanks
PS: In my case Galaxy S8
Click to expand...
Click to collapse
story is not completely same but my device is note 9 exynos and i did march patch BL is 5 and android 10 & 9 is sucks so need 8.1 but can't go back need serious help

Hey I'm Sam said:
story is not completely same but my device is note 9 exynos and i did march patch BL is 5 and android 10 & 9 is sucks so need 8.1 but can't go back need serious help
Click to expand...
Click to collapse
have you ever rosolved this ?
i have s9 note, want disperatly to downgrade to oreo for call recording. I feel cheated from samsung, what a waste of money....

Nemonavicusrino said:
have you ever rosolved this ?
i have s9 note, want disperatly to downgrade to oreo for call recording. I feel cheated from samsung, what a waste of money....
Click to expand...
Click to collapse
in the same boat as you, cube acr does record but the recording quality is very poor and the recording does not work when you are using Bluetooth headphones

Need help with recording
bilaliz said:
in the same boat as you, cube acr does record but the recording quality is very poor and the recording does not work when you are using Bluetooth headphones
Click to expand...
Click to collapse
Find something here, but i am not sure what i need, seem promising. I feel so cheated by this companies that put this restrictions on OUR HARDWARE. I do not understand, why something i pay today, dont work as espected tomorow, for SECURITY REASON. I want to asume risk and i do not know who is the owner. Me or samsung or google ?
https://forum.xda-developers.com/galaxy-note-9/help/enabling-native-call-recorder-csc-t3962224/page2
Espect day when phones is replaced by personal computer model. I want this OS on this hardware, with this app for calling and ...voila. I am at rage now : a 1000+ euro hardware canot record WHAT I SPEAK AND WHAT IS SPEAKED TO ME? if i put call on speaker and 10 person hear what is the diference...
Please help !

GuestD1009 said:
So I found the answer myself.
Apparently it is not possible to simply downgrade the Bootloader. I didn't fully dig into this, but to simply flash some image with Odin won't do the trick at least.
What works however is to downgrade to an older firmware with an older bootloader even if one keeps the newer bootloader on his device.
So what's the trick? One downloads the firmware file (.tar) which one wants to downgrade to and opens it with an archiver application (7zip). One extracts all the files to a folder and repacks them again in a .tar file but leaving every file out which ends on .bin (e.g. sboot.bin etc.). This .tar file can be flashed like any other firmware file via Odin and it should run through it without any problems.
I can not confirm that the downgrade works for every firmware version, but at least I could downgrade from Android 7 Nougat to 6.0.1 Marshmellow while the first one comes with the SW Rev 3 bootloader and the latter with SW Rev 2 bootloader. Again, I don't know how far into the past this works, e.g. if you can downgrade from 7 to 5.1.1 with this method.
Another option is always a Custom ROM (like this one for 5.1.1 for example) which doesn't check the Bootloader version.
I don't know if this method trips KNOX since I had tripped it already before figuring this out (very well could be, since you're not flashing a signed firmware file anymore...).
Click to expand...
Click to collapse
you sure this method works? i want to downgrade from 9 to 8. I am desperate now. But i don't know if it'll work. I've read thousands of words and all say it won't work.

S10 downgrade bootloader
I'm also in the same boat, Galaxy S10 (Exynos). Android 10 doesn't support PPTP VPN hotspot, and now my bootloader has been upgraded to U4. So yeah..

this seems helpful. are there anyone tried this on a s10 exynos?

ya not alone with an Samsung.....i'm on Sony Xperia 1 and after the update to Android 10 i have couple issuse with Soft restart out of nowhere everyday ones or more
dowangrade to Pie wasn't the problem but with Pie i went into an Gyroscope error....display isn't turning anymore i tried everything to get the sensor working but nothing helped
after updating to Android 10 Sensor running well

PlayJ004 said:
With a S7 Edge
Hello,
My phone has updated on the last version of Android 8.0.0 Oreo (01.12.2020), with the last version of Bootloader (7th). I want to downgrade my device to Android 6.0.1, but all version for this OS have BLv1, so I am in the same situation than you (but one gen. later). Can I downgrade my phone, with the same methode ? If so, can you explain this in detail or give me a custom OS ? Thanks in advance.
I tried with this methode and this doesn't work : Odin has shut down when I have started the process. What was wrong ?
Click to expand...
Click to collapse
same here

Me now with sm-p615 (tablet)

GuestD1009 said:
So I found the answer myself.
Apparently it is not possible to simply downgrade the Bootloader. I didn't fully dig into this, but to simply flash some image with Odin won't do the trick at least.
What works however is to downgrade to an older firmware with an older bootloader even if one keeps the newer bootloader on his device.
So what's the trick? One downloads the firmware file (.tar) which one wants to downgrade to and opens it with an archiver application (7zip). One extracts all the files to a folder and repacks them again in a .tar file but leaving every file out which ends on .bin (e.g. sboot.bin etc.). This .tar file can be flashed like any other firmware file via Odin and it should run through it without any problems.
I can not confirm that the downgrade works for every firmware version, but at least I could downgrade from Android 7 Nougat to 6.0.1 Marshmellow while the first one comes with the SW Rev 3 bootloader and the latter with SW Rev 2 bootloader. Again, I don't know how far into the past this works, e.g. if you can downgrade from 7 to 5.1.1 with this method.
Another option is always a Custom ROM (like this one for 5.1.1 for example) which doesn't check the Bootloader version.
I don't know if this method trips KNOX since I had tripped it already before figuring this out (very well could be, since you're not flashing a signed firmware file anymore...).
Click to expand...
Click to collapse
How on earth did you do that??
Which archive are you talking about when you say you unpack all the files and repack them without every .bin file?
I'm guessing the BL archive because that's the only one with a lot .bin files in it.
So I tried the BL_xxxx.tar.md archive and repacked it. But Odin would always get stuck at "file analysis..."
Also did you flash the modified BL first and then the AP, CP and CSC or did you flash it all at once?

I've got the same problem here. I want to downgrade my Galaxy S7 from Android 8.0 to Androud 7.0 but am unable to do so, to the point where I'm considering buying a completely new device just to have Android 7.0 again.

There is a way but...only Samsung's engineer are able to hack / trick this.
It is require special file to flashing in device then Sofware protection will be removed
Ask an Samsung Mobile Engineer if you have relatives.