How can i unlock the bootloader with SP Flash Tool?
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iam using lenovo k8 note, Suddenly my mobile restarted and stucked with logo screen, and some times i got error like dll image fail. for that i have searched in google and flashed cache.img file. Now phones is booting only in fastboot mode or stock recovery. so now i need to backup my data from phone.please guide me, how to get those data from internal memory.
Note: i have not rooted my phone.
Note: i have backup of full rom using sp flashtool which is encrypted. As i tried below answers which were not worked. So i given to service center which they are saying it is hardware issue. Now i want to get my data which is encrpted. is there any alternate solution to solve my issue. Please follow this link once which followed entirely
ROM is Android Oreo build number OMB27.43-70 and OEM unlocking is not enabled in Developer Settings.
What i have tried so far
- I have created my own scatter file with WwR MTK 2.51.
did a full ROM dump with SP Flash Tool (59 gb size), the partition starts from SYS0 to SYS34. i have splitted it in all of its partitions and saved to harddisk.
checked the recovery.img (from readback) with AIK it does unpack successful, so i am sure the scatter file is pointing to the right area of memory.
I read about Lenovo MTK Secure Boot and found a Download Agent for the Lenovo K8 Plus, which seems to work for my Lenovo K8 Note.
I tried all of these Download Agents, only the first will work
MTK_AllInOne_DA.bin DA_PL.bin DA_PL_CRYPTO20.bin DA_SWSEC.bin DA_SWSEC_CRYPTO20.bin
I have flashed back the stock recovery.img from SP Flash Tool, it was sucessful. so after that i tried to install twrp but got
ERROR: STATUS_SEC_IMGHDR_TYPE_MISMATCH(0xC0020029) [HINT]: verified boot is enabled. please download signed image (recovery-verified.img) or disable verified boot.
I followed this Tutorial and signed the twrp.img with some random key. Trying to flash twrp-3.3.1-0-manning-signed.img from SP Flash Tool gives the same error. got some information from hovatek
Message: BROM ERROR: STATUS_SEC_IMGHDR_TYPE_MISMATCH (0xC0020029) Meaning: You are trying to flash modified files to a device that only accepts signed or verified images Solution: Download and flash the official firmware (usually have -verified or -signed prefixes)
I gave up and decided to unlock the bootloader, but this doesn't work either
(because of OEM lock)
fastboot oem unlock < waiting for any device > (bootloader) Start unlock flow FAILED (remote: 'Unlock operation is not allowed') fastboot: error: Command failed
Therefore i tried to flash
system.img from here
i have set option --> downloaded --> selected tick for --> usb-checksum and storage-checksum (i tried with and without checksum)
first time flashing stucked at recovery.img which is showing 100%, after that got error, then showing
ERROR: STATUS_UNKNOWN_STORAGE_TYPE(0xc0040009) and Message: BROM ERROR: STATUS_DOWNLOAD_EXCEPTION (0xC0050003) Meaning: There was an interruption during writing to one or more partitions Solution: - Repeat flashing with the latest version of SP Flash Tool - Try using a different Port, USB cord and PC - Try flashing one partition at a time
taking a look into sp ft logs which shows
 [00:38:26:564109] [Tid0x00000be0] [info] data_mux receive timeout. #(data_mux.cpp, line:71) #(device_log_source.cpp, line:63)  [00:38:26:611019] [Tid0x00000be0] [info] Rx DA log timeout, continue. #(device_log_source.cpp, line:62)
i gave up now because flashing system.img stopped at 3%. this may caused by eMMC is probably weared out at this particular area, or the timeout is caused by a weak connection. i already tried different usb cables.
the goal is still to decrypt my data which is afaik only possible on the device itself. I have a backup of the encrypted partition so i can restore it to the phone after unlocking/factory reset, if neccessary. (at the moment all my data is still on the phone, i haven't performed a successful factory reset, yet)
fastboot oem unlock fastboot flash userdata C:\adb\userdata.img fastboot flash metadata C:\adb\metadata.img fastboot boot C:\adb\twrp-3.3.1-0-manning.img
please note chip-off method is not a solution, i already have a full ROM dump but it is encrypted.
The question is now, how can i unlock the bootloader with SP Flash Tool?
(as alecxs suggested it may possible to flash seccfg.bin + lk.bin from another Lenovo K8 Note, but i need help on digging more into this)