[Thinkpad Tablet Android Development] wilvanwil:
(TB-X704F (Wifi)) Lenovo Tab4 10 Plus

ok, this time I want to make it more clear, as I tried to flash my second tablet to Lineage 17,

but it didn't go as fast as I hoped for... trying to follow my post from last year.... :-o

this "manual" finally did it for me!(back up your tablet if you want to, I have no manual for that, google please)

before flashing anything:

1. go to Settings in your current Android(probably 7.1 or older Lineage), and in Developer Options(go to About Phone, then Build Number, tick that 7 times, then you should be able to find Developer Options...if not found google how to),

In Developer Options, make sure to unlock the bootloader: allow USB Debugging, and Allow OEM Unlocking.

Be aware in the end I have cleaned the tablet fully, so actually no OS(no Android, no Lineage) on it, only bootloader access, no problem. I got it working fine after that.

Go to the first page of this thread for these downloads....

2. Download Lineage OS 17.1, and a TWRP version (I used twrp-3.3.1-0-X704F.img).

Download OpenGApps(I used the nano version from here:

https://droidfilehost.com/download/download-open-gapps-fixed-arm64-10-0-20200131/ )

TWRP is the tool you will be actually starting from you pc/laptop, but will be showing on your tablet.

3. download Adb and Fastboot tool to you pc/laptop from here:

[OFFICIAL][TOOL][WINDOWS] ADB, Fastboot and Drivers - 15 seconds ADB Installer v1.4.3

15 seconds ADB Installer v1.4.3 ADB, Fastboot and Drivers What is this? This is All-in-One installer for 3 most needed PC tools for Android. No need to download big SDK for 3 small things. I originaly made it for my Kurdish friend AnGrY DuDe in...

xdaforums.com

Make sure you know the location of these files on your pc!!

(Would be a folder named ADB and Fastboot or similar) If I understand well, this has also drivers that will make sure your tablet is recognised by your pc/laptop.

(otherwise if tablet is not found, use the official site and get the correct drivers...

tablets :: a series :: tab4 10 plus - Lenovo Support LU

pcsupport.lenovo.com

)

4. Copy Lineage and OpenGApps to a microsd card.(leave as is, so .zip files). Put the microsd card in your tablet.

5. Locate your ADB(and fastboot) folder in Windows Explorer, and make sure to copy the TWRP file in that folder(twrp-3.3.1-0-X704F.img )

6. Shut Down the tablet. Then to get in the Fastboot mode: push the on/off button together with the volume + button, till you feel the vibration. The fastboot mode will show. You will read in green: START, and in red: FASTBOOT MODE.

Also in red it should show: DEVICE STATE - unlocked.

Connect the tablet with your pc/laptop with a USB-C cable, your pc should recognise your tablet(make a sound in my case), if not shown somehow when you click "This PC" in Explorer(Showing an icon with "Android" or your Tablet number(TB X704F in my case),

you will need to make sure the Lenovo drivers get installed.)

7. As soon as connected to your pc/laptop, you will be starting TWRP, the tool with which you will be performing the flashing of the Lineage OS 17.1 and the OpenGApps. The tablet still needs to be in Fastboot Mode. If not, make sure to go to step 6 again.

To start TWRP, go to the Explorer folder where you installed the ADB and Fastboot files, and where you copied the TWRP image file to.

Starting the TWRP app will be done by performing a command prompt. If you are an expert in using Commands, make sure to open a command prompt window, and navigate to the folder where the files are stored.(so in my case the files are in directory C:\adb>)

If you are not an expert in command prompt, go to Windows Explorer, click the folder where you have the files,(folder ADB, or ADB and Fastboot. as long as the adb, fasboot and TWRP files are there!!)

Click on the Explorer Address Bar, it will turn blue, just type "cmd", and hit enter, a Command Prompt window will open, which will be the exact one you will need.

(check how to:

2nd option, easy :-)) )

It should show: C:\adb> (or similar, depending on the exact folder name, I renamed my folder to "ADB" )

8. Now copy the prompt "fastboot boot twrp-3.3.1-0-X704F.img" , where twrp-3.3.1-0-X704F.img should be the exact file name you saved earlier in the folder.

hit Enter, and in a couple of seconds, TWRP will show on your tablet.

What I did first was, go to Swipe, then "Swipe to factory reset"

Then I did Advance Wipe, first ticked Cache, then "Swipe to wipe", no reboot, then also did that for Internal Storage, Data and System and Dalvik/Art Cache. Then I did a reboot, it should

reboot to the Fastboot mode.(point 6.)

For me this felt, like the tablet was quite clean, and ready to go ;-)

So then, the part of my post from last year that seems to make it work:

So start TWRP again with the prompt in the command prompt window.(beginning of step 8.)

(the next step for me, was the most important, so pls follow in detail)

9. TWRP: Make sure to untick the "auto reboot" in the general settings. Do everything in the settings now to prevent auto reboot.

In TWRP I went to the WIPE menu, Advanced wipe, selected everything except usb or SD card storage. (so system, data, internal storage, cache etc.). Swipe to wipe. (no reboot)

Also do "Format Data" where you need to enter "yes". Check everything except external/sd storage. Do NOT REBOOT.

Then to the Mount menu, I mounted the data, the system, cache, dalvik, vendor, AND I UNTICKED the Read only part.

Then you push "Select Storage", and I selected Internal Storage.

Back. (remember no rebooting!!!)

Then go to Install, Select storage, in my case the SD card, then FIRST(!!!) select the Lineage OS17 zip file, (I had no need to tick password verification, and untick reboot after flash)

Then swipe to confirm to flash it.***

DO NOT REBOOT YET, otherwise your Google OpenGapps will not get loaded!!!

Shouldn't take too long, go back, and then also flash the Open Gapps(or any compatible Google apps zip file you have)

(I had no need to tick password verification, and untick reboot after flash)

Then after that one, reboot, and keep your fingers crossed....

For me the reboot was fine and started with some google installations, then Lineage.

Google Play Store was there, and then you I could start downloading apps as normal.

*** When flashing Lineage OS 17.1 the bar should show progressing fairly quick, if you are waiting a minute and see no progress, then it's not working. Push the on /off button till the tablet restarts, go to step 8. again and prompt for the TWRP app, and try to clean/wipe everything again.

Perhaps first start with Wipe Cache only, then Internal storage only, data only etc. without rebooting.

For me, I had the idea the more I wiped and cleaned, the better I got it working finally.

From step 9. you really need to follow these in detail.

If something stalls in TWRP, just push the on/off button untill the tablet reboots,

I trust it still will go to Fastboot mode, and go to step 8. again.