| Concerning the writings in the download mode its a normal thing especially in new devices such as note8, s8, and s8+ so dont worry
For the phone to boot up after flashing stock firmware coming up from combination will take some time 2 or 3 min.
Try to choose close versions of combination and firmware to avoid being held on samsung logo
Be carefull to not flash userdata, pit so that the phone will not be resetted
So you are supposed to flash
( sboot, boot, system ,recovery , modem)
This will be enough |