[Samsung Galaxy Note 8 Questions and Answers] zifutanz:
hi guys, im lost and desperate need help right now

its been 4 days im looking for solution but no avail

please i need help to make my device back to normal again

device : Samsung Note 8 (XSP - Singapore Region) running One UI 1, Android 9. oem unlocked.

so here is the stories,

3 days ago, 22 Dec 2020.

i did factory reset on my device, and reboot

after that, my device lost the network, it detect my sim card but cant connect to network. signal lost.

i tried to reboot like usuall but still, no network available. lost the signal

but i can connect to wifi.

and i reboot it again, suddenly stuck at samsung logo

at first i thought this is easy just need to flash it with stock firmware

and i did, i download the stock firmware from sammobile, XSP - Singapore region.

with BL, CP, CSC, AP file, repartition not ticked. only tick the Auto Reboot and F. Reset time.

i choose the CSC file not HOME_CSC. so everything went well. PASS! green light in odin.

successfully flash my device, but weird, it is still wont detect any network or signal. i tried to automatically find network operator but it says "unable to connect" i tried everything and it says "NO NETWORK"

i did checked my imei , and its safe, its not blocked. but why my device still wont detect my sim card

and the i tried to reflash and flash and flash it again, several time hoping it will detect any network from my sim card after flashing but no avail

and then at the night, flash at 6th time, my device giving me more problem.

suddenly stuck at samsung logo bootloop. i went to recovery state, its says :

"E: FAILED TO MOUNT /EFS (INVALID ARGUMENT)

DM VERITY ERROR" stuff like that

damnn what problem again this time

im frustated already

and i flash it again with Pixel Experience rom hoping the problem will went away, but still , same results. "NO NETWORK"

i look it up in Settings - About - Status - Sim Card Status , its shown "DISCONNECTED"

my imei still there but just wont connect to network.

and then i tried to re-flash it again with stock firmware and again went straight into bootloop. with broken efs etc some****

im so mad and frustated, the problem keeps coming.

and then i found a temporary solution from @bluecub1st thread about the same problem :

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The following is a guide for repairing failed to mount efs and dm-verify fail (drk error)

We finally did it ~~~:D:D:D:D

Warning - We will not take any responsibility for your device. Follow the steps at your own risk. If your device is Knox 0, This guide would convert it into Knox 1 due to TWRP. For solutions that does not convert to knox 1 check out payed remote solutions. Everything on your device will be reset, including efs partition. You will need backup of efs.

Test on N950F binary 4 may work on other exynos models comment below if it worked for other samsung devices.

Problem Detail -

Bootloop with samsung stock firmware boot logo.

Recovery error E:Failed to mount /efs (Invalid argument) or dm-verity verification failed...

Device cannot boot into Factory binary or Stock Rom

Actions that could cause this problem -

Flashing a non-signed efs.img by odin

Corrupt flash of efs partition.

Note - Must have efs backup for device to work (very important)

Any error that cause bootloop would show in recovery required if

Files Required

Latest Odin (recommend 3.13)

Working Stock firmware and Combination file (same binary as bootloader)

PC

Winrar or 7zip etc

Solution for efs failed bootloop-

Extract Stock firmware AP file (rename .md5 to .tar)

Rename dqmdbg.img to efs.img (or smallest image must be smaller than 8000 KB). Extract Dqmdbg.img.lz4 so it’s just “Dqmdbg.img” and then rename it to efs.img and put that one in a tar. Other option is downloading a file that’s already made this way if your bootloader is binary 4, Saves you trouble of extracting / renaming: http://www.mediafire.com/file/589wucja9rk2v8f/efs.tar/file (if you download this file just move onto number 3)

Add file new efs.img into tar archive.

Flash tar as AP file in odin + download mode

Reboot download mode

Flash Combination with odin + nand erase option on Edit: suggest you to flash stock rom first and oem unlock, don't need to wait for 7 days if imei is 0000 skip combination step

Device Should boot into Factory binary

Use IME to restore imei using *#06# (or imei 0000 in stock rom) Edit: This step is not required if efs backup is restored successful

Your device should have dm-verify failed in recovery due to drk error

Continue drk bypass for dm verify error below to continue

Solution for dm-verify error (also known as drk bypass - but temporary read note)-

Extract Stock firmware AP file

Make a copy of boot.img and delete recovery.img

Note - if files is boot.img.lz4 format change name to recovery.img.lz4

Rename boot.img copy to recovery.img

Add all the files (including other files extracted) to tar.

Flash Modded AP file with BL, CP, CSC (nand erase not required)

The phone will boot into stock firmware

Note- cannot reboot, will stuck at dm-verify error again and need to flash modded AP again.

Wait 7 days to oem unlock phone or use 7 day bypass by changing dates (not always work, keep trying, don’t reboot, worked for Samsunguser932 Edit: Imei must be 0000)

Edit: oem unlock will fix drk - if not you must follow next step

Once oem unlock flash TWRP and restore efs backup Edit: if you haven't fixed imei fix now by *#06# with combination file

Flash stock firmware once again by odin (stock, not modded)

Done - phone is back to normal

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but at my case , the solution still failed,

yes it did success boot back into the system but still my network is still missing.

and he says restore with efs backup but he didnt attach the file to download the efs backup, how can i continue that step?

so i skip that step and just went to reflash it with stock firmware and the problem came again, it stuck in bootloop.

with efs broken ,

anyone here can share your efs backup ?

please i need it

im using samsung note 8 n950f XSP Singapore region

will appreciate your help a lot. thanks a lot