Help

[charis232]

I bought today the M3 ,Model number CPN-L09, EMUI 5.1 Android version 7.0 and
I want to go back to marshmallow ,I press and hold Volume Up,Volume Down and power button
after a few moments I get the error << Update failed>>.I follow the instructions putting the update.app on the sd card.The problem comes because my model is CPN and not BTV-DL09?
Any idea?. The build number is CPN-L09C100B012.
Thanks in advance

 

[Turuzzu]

I bought today the M3 ,Model number CPN-L09, EMUI 5.1 Android version 7.0 and
I want to go back to marshmallow ,I press and hold Volume Up,Volume Down and power button
after a few moments I get the error << Update failed>>.I follow the instructions putting the update.app on the sd card.The problem comes because my model is CPN and not BTV-DL09?
Any idea?. The build number is CPN-L09C100B012.
Thanks in advance

I don't know why you want to go back to marshmallow,
but if it to try rooting I think it is not necessary.
I'm trying to debrand a similar device from CPN-AL00 to CPN-L09
On this device I make unlock and root with success.
On CPN-AL00 I root successfully with Magisk.
I hope these info help you.
But ... about debranding currently I need about
OEMINFO / Custom.bin files for rebrand.
Can I ask you to provide me a backup
of yours (CPN-L09C100B012)?
Many thanks.