Question S21 Ultra stuck in boot loop

[Nabeel_Nabs]

So after the first May update I was getting the restars/crashes like everyone else.
The second May update I updated via ota 2 days ago, but overnight, I'm not sure what happened but the phone fails to boot, it just loops between samsung logos.
I need the data on the phone, so a factory reset isn't viable.

Any ideas or solutions on how I can at the very least backup some files from the storage?

 

[V0latyle]

Is your bootloader unlocked?

Can you try flashing the previous firmware? I don't think this will work because downgrade usually requires a data wipe, but it's worth a shot.

 

[Nabeel_Nabs]

Sorry for not saying, my phone was completely stock. I don't want to risk wiping in case a future update allows me to boot.

 

[mvikrant97]

So after the first May update I was getting the restars/crashes like everyone else.
The second May update I updated via ota 2 days ago, but overnight, I'm not sure what happened but the phone fails to boot, it just loops between samsung logos.
I have tried flashing the latest firmware via odin but it didn't help. I need the data on the phone, so a factory reset isn't viable.

Any ideas or solutions on how I can at the very least backup some files from the storage?

If you have already flashed the phone using odin then the data partition on the phone is erased.
You can downgrade the phone to previous security patch within the same binary.

For example
Let's say you have bricked the phone after installing the April Security patch on Binary 5
then you can downgrade to March Security patch Binary 5 which will fix your phone.

 

[Nabeel_Nabs]

I read using the home csc prevented a wipe?

Would downgrading from the latest may update to the April update work?

If you have already flashed the phone using odin then the data partition on the phone is erased.
You can downgrade the phone to previous security patch within the same binary.

For example
Let's say you have bricked the phone after installing the April Security patch on Binary 5
then you can downgrade to March Security patch Binary 5 which will fix your phone.

 

[st3chn0]

try using safe mode (hold volume + power button until device turns on) , you should be able to at least backup data.

if that doesnt work a downgrade wont help either, and you'll most likely will have to factory reset

 

[Nabeel_Nabs]

try using safe mode (hold volume + power button until device turns on) , you should be able to at least backup data.

if that doesnt work a downgrade wont help either, and you'll most likely will have to factory reset

Yeah I tried safe mode, it doesn't work

 

[st3chn0]

Yeah I tried safe mode, it doesn't work

well only way to recover data would be to root the device other than that it looks like a factory reset is going to be your only option

 

[Nabeel_Nabs]

well only way to recover data would be to root the device other than that it looks like a factory reset is going to be your only option

I can't root without unlocking the bootloader / wiping though, right?

Also can I rollback to the previous may or April update?

 

[illusion786]

Download samfw and use the soft unbrick option in samsung tab. Then boot to download mode and reflash previous firmware using odin or samfw.

Make sure to use home CSC to save data.

 

[Nabeel_Nabs]

Download samfw and use the soft unbrick option in samsung tab. Then boot to download mode and reflash previous firmware using odin or samfw.

Make sure to use home CSC to save data.

do you mean the samfw frp tool?
Also what does the fix soft unbrick function do? Is it something i can do without having to download their tool? I know how to use adb etc.

 

[illusion786]

Thats correct, the frp tool.

The soft unbrick option stops it from bootloop, then allows you to load the bootloader to enter odin to flash.

I wouldn't have a clue how you would stop it bootlooping via adb.... So yes that tool would be my only option.

 

[Nabeel_Nabs]

Thats correct, the frp tool.

The soft unbrick option stops it from bootloop, then allows you to load the bootloader to enter odin to flash.

I wouldn't have a clue how you would stop it bootlooping via adb.... So yes that tool would be my only option.

I can get into download mode already, repairing the firmware doesn't help.