Change the ROM on the Samsung S21

[fernandomelobr]

Hello,

I'm trying to change the ROM on the Samsung S21 from Operadora Claro in Brazil (ZTA), by a ROM from Samsung (ZTO).

I downloaded the firmware from the SAMMOBILE website, and used the file CSC_OMC_OWO_G991BOWO1AUB3_CL20962635_QB37982957_RE V01_user_low_ship_MULTI_CERT.tar.md5

The process finishes successfully in ODIN, but when you restart your phone it says: An unauthorized attempt was made to reset your device!

I also tried to reset with the debug mode active, even so it happens just like the step above.

Could someone help me solve this?

[henklbr]

Hello,

I'm trying to change the ROM on the Samsung S21 from Operadora Claro in Brazil (ZTA), by a ROM from Samsung (ZTO).

I downloaded the firmware from the SAMMOBILE website, and used the file CSC_OMC_OWO_G991BOWO1AUB3_CL20962635_QB37982957_RE V01_user_low_ship_MULTI_CERT.tar.md5

The process finishes successfully in ODIN, but when you restart your phone it says: An unauthorized attempt was made to reset your device!

I also tried to reset with the debug mode active, even so it happens just like the step above.

Could someone help me solve this?

Hi there

What files did you flash to your device?

Note: you can't change the CSC from ZTA to ZTO, because both CSC's are part of Multi-CSC OWO!

[fernandomelobr]

Hi there

What files did you flash to your device?

Note: you can't change the CSC from ZTA to ZTO, because both CSC's are part of Multi-CSC OWO!

Hello,

I transferred all of these here through ODIN:

[fernandomelobr]

I bought my cell phone from Claro (ZTA). It came with several apps installed that I don't want on my phone. Not to mention that Claro takes a long time to release updates.

I did the same procedure in the past, with my S20, with the S10. It always worked.

Now I am repeating the same steps, but it does not change from ZTA to ZTO.

[henklbr]

I bought my cell phone from Claro (ZTA). It came with several apps installed that I don't want on my phone. Not to mention that Claro takes a long time to release updates.

I did the same procedure in the past, with my S20, with the S10. It always worked.

Now I am repeating the same steps, but it does not change from ZTA to ZTO.

As I said: you can't change the CSC from ZTA to ZTO, because both CSC's are part of Multi-CSC OWO

[fernandomelobr]

Which one can I use to replace the operator's one and leave the direct one from samsung?

[henklbr]

Which one can I use to replace the operator's one and leave the direct one from samsung?

You can't change your current CSC

You could ask a Samsung Service Point if they want to change the CSC from ZTA to ZTO for you, but I doubt they will do that

[fernandomelobr]

You can't change your current CSC

You could ask a Samsung Service Point if they want to change the CSC from ZTA to ZTO for you, but I doubt they will do that

Was even the S20 version possible? Because I did it on my S20 and S10. Is it a new lock?

[henklbr]

Was even the S20 version possible? Because I did it on my S20 and S10. Is it a new lock?

Those devices had probably different Multi-CSC's...

Why didn't you buy a ZTO (UN-branded) device?

[fernandomelobr]

Those devices had probably different Multi-CSC's...

Why didn't you buy a ZTO (UN-branded) device?

Because of the discount I have on my plan with the operator. Every year I change my cell phone with Claro. I can always change the ROM, only this time on the S21 that I am not getting.