[Blu Vivo XL] smith901:
I must note: I use linux. I only used Windows because SPFT Linux version gave me a chip mismatch error I couldn't fix easily.

1: Please read. It explains what problems might arise. Especially post #6 and #13.

2: There are 2 versions of the scatter file. The MT6735 version is what I used successfully. The MT6737Tmod version is what comes from post #6 & #13.

3: Please use each scatter file to Readback your boot and recovery partitions first, renaming as fit, so you can have a backup BEFORE ANYTHING. Then test unpacking them to see if everything went correctly. Then readback every partition in the scatter file so you don't have to depend on the stock ROM for a backup. I didn't and it led me to take this route.

3: Seem to be a difference in the naming of the scatter file and sizes of system, cache, and userdata inside from the stock ROM and what works..

4: DO NOT choose Format+Download until you know which scatter file works, unless you want to chance a Hard Brick.

5: Wiping the dalvik and cache in stock recovery before flashing TWRP seems to be the best thing to do to avoid boot loops or a hung boot.

THIS ROOT PROCESS WAS DONE OVER THREE DAYS OF CAR WORK, DRIVING, FAMILY, AND COMPUTER WORK. MOST OF THE TIME SPENT WAS THIS MORNING TRYING TO GO TO SLEEP. DIDN'T HAVE TIME TO DOCUMENT AND TAKE PICTURES. THIS WRITE-UP IS FROM WHAT I REMEMBER DURING THIS PROCESS. IF I CAN REMEMBER SOME VAGUE DETAIL THAT YOU NEED, GOOD. IF NOT, DON'T STRESS ME. THE HARD PART IS DONE. A GOOGLE SEARCH OF SOME OF THESE PROGRAMS WILL GET QUICKER RESULTS IF YOU DON'T HAVE THEM. THE MAIN THING NEEDED FROM MY RESEARCH WAS THE SCATTER FILE. LINKS FOR SCATTER FILE AND RECOVERY IMAGE ARE BELOW.

Looking for a way to root first day getting this phone in February. Read this post last Tuesday about MT67xx rooting, thanks lsemprini. Spent two days finding which versions of the programs work with this phone, already had the ROMs, drivers, and tools. Dove right in.

I downloaded the ROM from needrom. Scatter file was unusable. Wrong chip error. Phone reads MT6735 scatter file read MT6737. Did a manual diff. Used

SP Flash Tool v5.1524

to flash, formatted instead of downloading by mistake, cord got pulled, Hard brick. Fought with Windows7 to get drivers to recognize a hard brick. Still don't know how I did it but it read then flashed. Looked like another hard brick but SPFT would recognize it for the Memory Test. I just held power+vol_down with just charging block power to get it to come on. Sometimes just one of the buttons was enough to get it to power on and start a bootloop. Took two minutes sometimes. Flashing the wrong recovery led to bootloops. Starting SP Flash Tool and plugging in the USB to the phone as soon as it powers off during a loop will let the preloader "register" and the images to be flashed. Flashing from a stock ROM will lead to IMEI being erased. Used

SN Write Tool v1.1716

to write the IMEI numbers. Got them from the side of the box. The MD1_DB and AP_DB files needed are in the stock rom.

Ported TWRP, credit to jemmini for the post https://xdaforums.com/vivo-xl/development/recovery-t3311601. Used that recovery as a base. Ported according to the myriad of guides that I have been reading over the past few days. None of them worked as instructed, had to modify trial and error style. Finally got TWRP to read the internal partitions AND remain after a reboot. A lot was going on when I did this. Not sure if I formatted before, I remember flashing a lot of because of something. I mounted the system just in case & flashed SuperSu from chainfire's website, no formatting afterwards. Rebooted and installed SuperUser and BusyBox. I tried adb and fastboot. They work but not for everything. Hooked phone up to computer with debugging enabled.

adb root

gives a shell, no errors unlike before. Edit: ADB won't let me start as root anymore.

Needed files

Blu Vivo XL2 TWRP 3 Recovery

MT6735 Scatter File

MT6737T Scatter File

BLU Vivo XL2 V0070UU Stock ROM if you don't have a backup of your partition images.

Step 1

Install Minimal ADB and Fastboot and USB VCOM drivers.

Download SP Flash Tool, SN Write Tool, scatter file, and twrp3.0 to a working folder.

Download SuperSu zip & SuperUser apk then put them on your SD Card.

Install SD card into phone.

Step 1.A For Full ROM Flash and IMEI Write

Download Stock ROM and extract to working folder.

Move twrp3.0 to ROM folder.

Step 2

Install SP Flash Tool and SN Write Tool and run.

Step 3 To flash TWRP only

Reboot phone to recovery then wipe cache and dalvik. Can't remember if it is a dalvik option in the stock recovery now.

Power off phone. Make sure it is not plugged up to the computer.

IN SP Flash Tool:

Load scatter file that works from working folder.

Make sure download only is selected in drop down menu.

Check only the recovery partition box and click the name of the recovery file on the same line.

Browse to TWRP recovery image and select.

Click the Download button with the green arrow.

Plug phone into computer and wait until window with OK pops up. Success.

Step 3.B OPTIONAL

Select format and flash all using stock ROM or images backed up from your phone.

Stock ROM must be extracted and custom recover put into same folder and renamed to "recovery.img" to make

everything automatically load.

Click the Download button with the green arrow.

Plug phone into computer and wait until window with OK pops up. Success

Step 4 Only needed when formating+downloading ROM

With phone still powered off and unplugged, write IMEI numbers using SN Write Tool.

Step 4.A

Click System Config.

Select IMEI in Write Option Area.

Make sure IMEI Checksum and Dual IMEI are checked.

Load MD1_DB and AP_DB files from ROM folder.

Click Load Modem DB from DUT box.

Click Save.

Step 4.B

Click Start.

Input your IMEI numbers from box.

Click OK. Success

Step 5

Boot to recovery.

Swipe to make permanent.

Wipe dalvik and cache.

Flash SuperSu..

Reboot.

Install SuperUser apk and BusyBox of your choice.

Step 5.A

If SuperUser apk or any app that ask for root permission cannot get it, reboot to recovery.

Mount system partition: Shouldn't matter but it worked for me.

Flash SuperSu zip again.

Reboot.

Install SuperUser apk and BusyBox of your choice.

ENJOY