Can't unlock bootloader I'm trying to unlock the bootloader of my tablet for hours now.. There's no solution out there that worked for me. I've already tried:


fastboot oem unlock (the tablet responses with a question screen where I can select "yes, unlock bootloader" and "no, don't unlock bootloader", but when I select yes it responses with an error "Unlock failed - Err:0x7000")
fastboot oem bootloader unlock (this command stucks at "...")


I also tried to flash custom recovery so I could get around this but now I'm stuck in a bootloop.. I have a backup of the stock recovery, but I can't flash it either..

fastboot flash recovery recovery_stock.img responses with:

sending 'recovery' (10240 KB)...
OKAY [ 0.417s]
writing 'recovery'...
FAILED (remote:
Security deny - Err:0x2017
)
finished. total time: 0.430s


I know that Security deny - Err:0x2017 is because of unlocked bootloader...

Tablet-Information:

Name: Medion Lifetab S8312

Processor: Mediatek MT8392
Generic answer: The errors in the unlocking process (and especially security errors like yours) generally mean that the device vendor does not allow unlocking. Some device vendors allow it by personally issuing unlock codes (through individual support requests), but it's getting rare nowadays.

Unfortunately the only way is the "old" way, which is to "break into" the device, which usually requires a specific bug on a specific version of Android ROM using a specific program. Since people hardly play with such exploits nowadays and your device seems to be a rather unpopular one your chances to unlock it are sadly very low.

You may try to contact the vendor, if they still exist.