Database Users

Help withAndroid N Preview 5

Hi Guys, i have 1 little problem.
im on the last Android N Preview 5 and i wannt to root it.
i have downloaded SuperSU 2.76 and TWRP 3.0.2.0
I rebooted to bootloader flashed thw twrp via Terminal, now i wanna boot into recovery because of the SuperSU zip, but i am stucking on TWRP Logo.
Phone is working normal, but i cant enter into recovery, anyone else has the same problem?
Thanks and best Regards,
Taker

You have to flash another version of TWRP... But, dude, i'm on the exact same case, same preview, and i can't get it to work. TWRP doesn't seem to work :/ I always got the god damn "no command" even if i follow some of the tutorials here...
EDIT : Try flashing the 3.0.0 or 3.0.1, and when all will be working (if you achieve, tell me how xD) update it.
EDIT 2 : I may find something, i'll let you know !

TWRP doesnt work with the developer previews without modifying the boot image.
If you want to root, you can use CF-Auto root.
You will still have the stock recovery.

Taker18 said:
Hi Guys, i have 1 little problem.
im on the last Android N Preview 5 and i wannt to root it.
i have downloaded SuperSU 2.76 and TWRP 3.0.2.0
I rebooted to bootloader flashed thw twrp via Terminal, now i wanna boot into recovery because of the SuperSU zip, but i am stucking on TWRP Logo.
Phone is working normal, but i cant enter into recovery, anyone else has the same problem?
Thanks and best Regards,
Taker
Click to expand...
Click to collapse
This is a known issue, Search the forum for the resolution. Basically TWRP won't work on the Android N on Encrypted device.

The solution is pretty simple. You need to decrypt your device's storage. TWRP currently doesn't work with encrypted N preview.
This could be easily done by flashing the modified boot image, that will disable forced-encryption. After that, you will need to format the current userdata partition to decrypt the storage.
Code:
fastboot format userdata
fastboot format cache
Once that is done, you can flash TWRP and then use SuperSU to root.
Another way to direct root is by using Cf-Auto-Root. But I am not sure about that specifically. While some users have succeeded, there are a few who have failed to root using Cf-Auto-Root.

Just use CF-Auto Root, it will do all the things.
Make sure you have unlocked your Bootloader and downloaded the good version of CF for your device.
Reboot your phone in bootloader mode, plug it to a computer, and just open the .bat (if you're on windows, or the equivalent for Mac / Linux). It will install SuperSU. When it's done, don't forget to download the TWRP Manager on the Playstore, and you'll have a working Recovery ! I did that, i know have a rooted nexus 6P on Android N preview 5
Also, lot's of Root's only apps will not work properly, because lots of changes took place on Android N. So make sure you follow some guide out there (exemple : Ex Kernel don't work if you don't tweak some things, same with Ad Away, so make sure you're googling)

I followed the premise of this thread here so all credits go to the OP http://forum.xda-developers.com/showthread.php?t=3410906 I flashed the latest Marshmallow vendor.img via fastboot, then flashed TWRP via fastboot. Booted into recovery from the bootloader then side loaded supersu using adb side load in TWRP. After that I rebooted to bootloader from TWRP and fastboot flashed the DP5 vendor.img and recovery.img. All is working well.

TWRP bootloop after flashing TWRP Solved

Don´t know if anybody had this kind of Problem before. Couldnt find anything.
Was on Stock V image with cutom kernel flashed via fastboot and SU flashed via fastboo boot to root.
Problem:
bootet TWRP via fastboot with newest drivers. Flashed RC via booted TWRP.
Wanted to reboot system, but was stuck in a TWRP bootloop. No chance to boot into bootloader also. Even tried changing slots in twrp but still only bootloop to twrp.
Than I thought about sideload because that's what I did with latest ota image from Google.
Here is what I did:
sideloaded the ota.zip via TWRP from PC "adb sideload ota_file.zip" ota_file should be the name of your ota file
It gave me an error, but after rebooting system all fine again. Back to stock V and bootloader is there again.

Easier thing to do is flash boot.img from the factory image to boot_a and boot_b if you are having issues.
This problem occurs when you flash TWRP if you have root installed. To avoid, remove root before installing TWRP.
Oh, I should mention to get into bootloader from TWRP, simply use the adb command "adb reboot bootloader". Should work, worked for me.

I just have avoided flashing TWRP altogether. I rarely need to flash anything, so it can wait until I am at work or home to use a PC to BOOT TWRP each time I need it, instead of flashing it.

Nitemare3219 said:
I just have avoided flashing TWRP altogether. I rarely need to flash anything, so it can wait until I am at work or home to use a PC to BOOT TWRP each time I need it, instead of flashing it.
Click to expand...
Click to collapse
Until it gets a little more stable on the Pixel, this is probably a good idea.

Good idea. But I M sometimes flashing when I am at or on the way to work.
Flash junkie needs his daily dosis

mikaole said:
Don´t know if anybody had this kind of Problem before. Couldnt find anything.
Was on Stock V image with cutom kernel flashed via fastboot and SU flashed via fastboo boot to root.
Problem:
bootet TWRP via fastboot with newest drivers. Flashed RC via booted TWRP.
Wanted to reboot system, but was stuck in a TWRP bootloop. No chance to boot into bootloader also. Even tried changing slots in twrp but still only bootloop to twrp.
Than I thought about sideload because that's what I did with latest ota image from Google.
Here is what I did:
sideloaded the ota.zip via TWRP from PC "adb sideload ota_file.zip" ota_file should be the name of your ota file
It gave me an error, but after rebooting system all fine again. Back to stock V and bootloader is there again.
Click to expand...
Click to collapse
I know its already solved, but here is what helps (for future):
Just flash SuperSU (latest Version)
Done. This will patch the boot.img so your phone boots in the OS again.

Shadow of Destiny said:
I know its already solved, but here is what helps (for future):
Just flash SuperSU (latest Version)
Done. This will patch the boot.img so your phone boots in the OS again.
Click to expand...
Click to collapse
I have this issue and flashing supersu didn't fix my problem. Will go to factory image flashing.

Shadow of Destiny said:
I know its already solved, but here is what helps (for future):
Just flash SuperSU (latest Version)
Done. This will patch the boot.img so your phone boots in the OS again.
Click to expand...
Click to collapse
Thanks! This worked for me.

EDIT: Never mind, I missed the comment guiding ppl to flash SuperSU. I suppose that when this thread was posted, that SuperSU was still being used instead of Magisk, so solution is essentially the same thing I'm recommending.
I think this thread is missing the much easier solution here:
I just ran into this issue with my Pixel 2 XL when I tried to update my TWRP version from 3.2.1-2 to 3.2.3-0. Here's how it went:
1. Downloaded the TWRP zip, md5 and so on from the official TWRP website for the Pixel 2 XL
2. Booted to TWRP and installed / flashed the zip of TWRP 3.2.3-0
3. Wiped dalvik and then chose Reboot to System from TWRP -- the phone booted right back into TWRP
4. Tried again to reboot the same way. Same result.
5. Installed / Flashed the 3.2.1-2 TWRP zip which was still on my phone, in order to revert to the previous version, and then Rebooted to System -- same result
6. Flashed 3.2.3-0 zip again, then flashed the Flash Kernel that I've been using, and then Flashed the Magisk v16.0 zip that I used to root, then chose Reboot to System -- AND IT WORKED; the phone booted normally and now I'm updated to the latest TWRP successfully.
tl;dr - The solution is to flash Magisk again after updating TWRP. Pretty sure this goes for kernel updates too.

cognitivedissonance said:
EDIT: Never mind, I missed the comment guiding ppl to flash SuperSU. I suppose that when this thread was posted, that SuperSU was still being used instead of Magisk, so solution is essentially the same thing I'm recommending.
I think this thread is missing the much easier solution here:
I just ran into this issue with my Pixel 2 XL when I tried to update my TWRP version from 3.2.1-2 to 3.2.3-0. Here's how it went:
1. Downloaded the TWRP zip, md5 and so on from the official TWRP website for the Pixel 2 XL
2. Booted to TWRP and installed / flashed the zip of TWRP 3.2.3-0
3. Wiped dalvik and then chose Reboot to System from TWRP -- the phone booted right back into TWRP
4. Tried again to reboot the same way. Same result.
5. Installed / Flashed the 3.2.1-2 TWRP zip which was still on my phone, in order to revert to the previous version, and then Rebooted to System -- same result
6. Flashed 3.2.3-0 zip again, then flashed the Flash Kernel that I've been using, and then Flashed the Magisk v16.0 zip that I used to root, then chose Reboot to System -- AND IT WORKED; the phone booted normally and now I'm updated to the latest TWRP successfully.
tl;dr - The solution is to flash Magisk again after updating TWRP. Pretty sure this goes for kernel updates too.
Click to expand...
Click to collapse
This is a Pixel XL forum.

Homeboy76 said:
This is a Pixel XL forum.
Click to expand...
Click to collapse
Aren't the two systems (Pixel OG and Pixel 2) extremely similar? If they're not, then my advice should be ignored for anyone using the Pixel OG.

No OS installed. TWRP cannot flash new custom ROM

Hello,
I have a big problem. I don't know what to do.
I wanted to make a clean install of OxygenOS 4.5.8 and so i downloaded it, did it on SD card together with Magisk and no_verity_op5.zip (because i read that this decrypt the data).
So i cleand data and installed no_verity_op5.zip via TWRP, but when i wanted to reboot it takes way to long (i waited 30minutes but it stays on boot circle)
After that i booted into TWRP and decided to made a factory reset and to install OxygonOS 4.5.8 in a clean version. But it was not possible anymore!
When i want to install the .zip it says Patching system image unconditionally... and it loads. after the blue is full it says:
writing static_nvbk image...
patching firmware images...
script succeeded: result was [1.000000]
And when i want to boot into system it says no OS installed.
I tried also to flash this rom or even any other custom rom through ADB Sideload but it does not work. Same like above..
What can i do? I do not know what to do
I hope my phone is not bricked.
Thank you for any suggestion.

Go to oneplus 5 official download page, download stock recovery and latest stock firmware and follow instructions on the download page.... But first with TWRP take a backup of all your data because restoring stock firmware will ERASE everything... Don't panic it will works

First off, don't panic! you're not bricked as long as you can reach your bootloader and recovery.
This happened to me as well and luckily the fix is easy!
You probably tried to flash the OxygenOS build from the Oneplus downloads right?
Somehow these won't flash properly through TWRP and you must therefore also flash the Oxygen recovery image listed in the downloads.
Here are some steps that'll fix your problem.
1 - Backup all of your private data from internal storage because flashing OxygenOS will WIPE/ENCRYPT all data on your device.
2 - Go to the Oneplus download center and download both the latest OxygenOS and it's appropriate recovery:
http://downloads.oneplus.net/oneplus-5/oneplus_5_oxygenos_4.5.8
3 - Boot into your bootloader and flash the stock recovery you just downloaded. (fastboot flash recovery <recovery>.img)
4 - Boot into the Oxygen recovery and flash OxygenOS.
This should get you up and running again.
Once you get tired of OxygenOS simply reboot back into your bootloader and flash TWRP and any rom of your liking.
In the future if you want to flash OxygenOS from TWRP you have to grab a build from XDA I guess. I'm not entirely sure why flashing from within TWRP won't work with stock OOS but I believe it expects to be flashed from withing the stock recovery.
I'm pretty confident this will solve your problems.
Please backup your data first though, don't want anything to get messed up in there!
Good luck!

Ok thank you.
i will try it.
So you are right, i tried to install OxygenOS with TWRP.
So is it not possible to have official OxygenOS with TWRP, Magisk and Root?
So i cannot backup OxygenOS with TWRP?

manuelbvb said:
Ok thank you.
i will try it.
So you are right, i tried to install OxygenOS with TWRP.
So is it not possible to have official OxygenOS with TWRP, Magisk and Root?
So i cannot backup OxygenOS with TWRP?
Click to expand...
Click to collapse
It is possible to have both OxygenOS and TWRP for sure!
Only a clean flash from a non-encrypted state in TWRP seems to break stuff. You can use a modified OOS build from the forums.
TWRP can indeed backup your OOS install so that shouldn't be a problem.
The only exception seems to be flashing a clean install of OxygenOS (from Oneplus Download center) through TWRP.
Other than that everything works as expected.

Ok thank you.
So i will follow you instructions and i hope it will work.
And i think so.
And after it i will install TWRP again (because i need the backup tool), i will install magisk. will this work?
So i can use everything as in a custom rom, but cannot make a clean install? So official Oneplus OTA will work with TWRP or not?
Thank you soooo much!

Also, Magisk/root works just fine on OxygenOS.
Once you flashed OOS from the stock recovery and have everything set up simply boot into your bootloader and flash TWRP.
From there you flash Magisk and everything should be fine.
OTA's from Oneplus also install fine through TWRP as long as you go into Magisk and uninstall 'root' first. When OxygenOS tells you there's an update simply remove Magisk as I said above and it'll update fine.

Ok thank you!
It worked!!!!! I am very happy!
So i will now install TWRP, and then magisk (newest version).
I have a question, because the last time i installed magisk it did not fully work.
If i install it i have root or? But how can i get saftynet in magisk?

manuelbvb said:
Ok thank you!
It worked!!!!! I am very happy!
So i will now install TWRP, and then magisk (newest version).
I have a question, because the last time i installed magisk it did not fully work.
If i install it i have root or? But how can i get saftynet in magisk?
Click to expand...
Click to collapse
First off! YAY!! glad it worked out!
Be sure to use the TWRP build from the twrp.me website. The one listed on these forums are 'unofficial'. Not saying those are bad, but the official one has a pretty impressive track-record.
After flashing Magisk you are root-enabled so yeah, congrats you are now root! In order to pass safetynet you must enable 'magisk hide' in the magisk manager (the app that should now be installed on your phone).
If you do not have an app called 'magisk manager' then you can download this app from the magisk forums. It should however install itself while flashing the Magisk zip. So assuming you have it installed find the 'magisk hide' service and enable it.
From my experience you sometimes need to reboot in order for it to pass safetynet check.
Glad it all worked out for you!

Everything worked!
Now i have OxygenOS 4.5.8 (with OTAs in future), magisk + root + saftynet and i can install something throug TWRP and backup.
SO PERFEKT.
You are a hero

manuelbvb said:
Everything worked!
Now i have OxygenOS 4.5.8 (with OTAs in future), magisk + root + saftynet and i can install something throug TWRP and backup.
SO PERFEKT.
You are a hero
Click to expand...
Click to collapse
That's great to hear!
Enjoy and take care!

no os
sideloaded zip for rom in twrp, says successful but then no os installed and I can't find the zip anywhere in twrp. help :]

xda___ said:
sideloaded zip for rom in twrp, says successful but then no os installed and I can't find the zip anywhere in twrp. help :]
Click to expand...
Click to collapse
Can't you just connect your phone to your PC and use MTP for the file transfer? Make sure to have MTP disabled under TWRP-> Mount -> Enable MTP

Zocker1304 said:
Can't you just connect your phone to your PC and use MTP for the file transfer? Make sure to have MTP disabled under TWRP-> Mount -> Enable MTP
Click to expand...
Click to collapse
I tried, windows recognizes my phone, but when I try to transfer files it it says device is not available or has been disconnected (something like that...)

xda___ said:
I tried, windows recognizes my phone, but when I try to transfer files it it says device is not available or has been disconnected (something like that...)
Click to expand...
Click to collapse
Well just flash a different twrp via fastboot flash recovery *path to file*

Re-Rooting 1+5 after OS 5.1.1 Update

So I tried updating to Oxygen is 5.0 ran into an install issue, stuck in boot loop. Lucky I had done a Nandroid back up and restore everything. The other night I decided to update to 5.1.1 thinking why not get Android 8.1.0 on my AWESOME phone. Downloaded update, placed in internal storage, booted into TWRP to do a Nandroid back up (due to issues with past update). Back up failed needed to clean drive. So I decided, phone works in Android 7.1.1, why can't what's not broken. Rebooted phone and somehow the update activated. I freaked since last time it failed and not stuck in a loop. This time update was successful but still got stuck in a boot loop. I plugged my phone to my computer and noticed all my files were gone on their install storage, no files / foldersI recognized (e.g. DCIM, DATA, DOWNLOAD, etc). Emailed One Plus and chatted with them. TWRP was gone and was back on stock recovery. Since all was lost I was asked to "Erase All". I did, rebooted and I'm now on 8.1.1 but all my stuff was lost. So I've done since searching and found FlashFire do to a Nandroid backup but need root. So my question is...
Can I re-root my phone without using TWRP but stock recovery and use FlashFire for my back ups? I am not going to flash custom ROM but if I need to flash something, wouldn't stock ROM flash anything on my phone (Magisk)?
If so, can anyone provide me with assistance on re-rooting my phone without TWRP.
Thank you

As far as i know you can't flash anything with stock recovery so you can't root. After flashing the stock os is normal that twrp is been erased by the stock. Just re flash the twrp. I mean, maybe i didn't get the problem, why you can't reflash twrp? If you do that flash twrp codeworx Universal with fastboot in the bootloader, boot in twrp, wipe cache/dalvik, flash magisk 15.3, wipe cache/dalvik, reboot system, update magisk to 16 with the app. I do that way and it worked

Hi
To root your OnePlus 5, you must to follow carefuly the steps below and take your time.
1 - Make a full backup of your data
2 - Unlock the bootloader (Note that'll erase your phone)
3 - Install another recovery : TWRP. This one : https://sourceforge.net/projects/ch...-20180414-codeworkx-cheeseburger.img/download
4 - Flash the full rom Oxygen OS 5.1.1 : http://otafsg.h2os.com/patch/amazon...23_OTA_034_all_1804201219_3824995916a49ee.zip
5 - Install magisk : https://github.com/topjohnwu/Magisk/releases/download/v16.0/Magisk-v16.0.zip
6 - Clear cache / Dalvik
7 - You're all done, reboot the phone
8 - Once your phone has booted up, install magisk manager : https://github.com/topjohnwu/MagiskManager/releases/download/v5.7.0/MagiskManager-v5.7.0.apk
Check this tread, that'll help you as well : https://forum.xda-developers.com/oneplus-5/how-to/oneplus-5-unlock-bootloader-flash-twrp-t3624877

vanzant83 said:
As far as i know you can't flash anything with stock recovery so you can't root. After flashing the stock os is normal that twrp is been erased by the stock. Just re flash the twrp. I mean, maybe i didn't get the problem, why you can't reflash twrp? If you do that flash twrp codeworx Universal with fastboot in the bootloader, boot in twrp, wipe cache/dalvik, flash magisk 15.3, wipe cache/dalvik, reboot system, update magisk to 16 with the app. I do that way and it worked
Click to expand...
Click to collapse
Hello, thanks for the info and yes, I did try flashing Magisk with stock recovery, while waiting for a reply and can confirm installation failed. So if I reflash TWRP, flashing Magisk using TWRP will work. Therefore, do you have instructions (step-by-step) on how to install TWRP. I have downloaded the latest TWRP image from their website (twrp-3.1.1-1 cheeseburger) onto my desktop. Bootloader is already unlocked as I was previously rooted under Android 7.1.
Thank you.

https://forum.xda-developers.com/oneplus-5/how-to/oneplus-5-unlock-bootloader-flash-twrp-t3624877
This is the official guide step by step, scroll down until you find "flashing twrp" if you had already unlocked the bootloader ( you already did that right??? xD). Anyway about the recovery and magisk version. The guys in the 5.1.1 thread advised to flash magisk 15.3 instead the 16 and only after the system reboot to make the upgrade to 16 with magisk app (dunno why). But when i tried to do that the last version of twrp (3.1.1-1) failed the flash. So i flashed the twrp 3.1.1-0-universal and 15.3 magisk. I can confirm this combination work, i can't tell for other combinations.

vanzant83 said:
https://forum.xda-developers.com/oneplus-5/how-to/oneplus-5-unlock-bootloader-flash-twrp-t3624877
This is the official guide step by step, scroll down until you find "flashing twrp" if you had already unlocked the bootloader ( you already did that right??? xD). Anyway about the recovery and magisk version. The guys in the 5.1.1 thread advised to flash magisk 15.3 instead the 16 and only after the system reboot to make the upgrade to 16 with magisk app (dunno why). But when i tried to do that the last version of twrp (3.1.1-1) failed the flash. So i flashed the twrp 3.1.1-0-universal and 15.3 magisk. I can confirm this combination work, i can't tell for other combinations.
Click to expand...
Click to collapse
Hello, I finally got some time to re-root my phone and was reading the instructions you provided and clicked on the download but they are TWRP 3.2.1.x and Magisk 16. Do you have the links for the files you used
Grazie

jmoricone said:
Hello, I finally got some time to re-root my phone and was reading the instructions you provided and clicked on the download but they are TWRP 3.2.1.x and Magisk 16. Do you have the links for the files you used
Grazie
Click to expand...
Click to collapse
Sorry man i typed wrong, the one i meant was 3.2.1-0 Universal codeworkx, the fourth from up to down. About 15.3 magisk i dunno where you can find It, maybe try some google research, otherwise i can send It to you by email, is a little file

Try this link, get the ZIP file from the version you want: https://github.com/topjohnwu/Magisk/releases/
In case you need, this the official section: https://forum.xda-developers.com/apps/magisk

vanzant83 said:
Sorry man i typed wrong, the one i meant was 3.2.1-0 Universal codeworkx, the fourth from up to down. About 15.3 magisk i dunno where you can find It, maybe try some google research, otherwise i can send It to you by email, is a little file
Click to expand...
Click to collapse
Hey there, sorry for the late response..but thank you for the assist..phone is rerooted..all is good..thanks again

What is update process for OP6T 9.0.16 > 10.3.3 rooted [Global]

I have OP6T OxygenOS 9.0.16 and I would like to update it to the latest 10.3.3 with root.
What should be my process of doing so? I have not been in touch with rooting for the past 3 years so I don't want to mess things up. Another note is that while I am on OxygenOS 9.0.16 I tried to root it which was failed, but now few banking and calling apps such as TextNow thinks that my phone is rooted and they can not run -- but my phone is not properly rooted according to root verification apps.
Please tell me how should I do the update to the latest version from this point and then I would like to unlock bootloader and install recovery and root it as well.
Please advice.
BTW my OP6T is global

a4abbas said:
I have OP6T OxygenOS 9.0.16 and I would like to update it to the latest 10.3.3 with root.
What should be my process of doing so? I have not been in touch with rooting for the past 3 years so I don't want to mess things up. Another note is that while I am on OxygenOS 9.0.16 I tried to root it which was failed, but now few banking and calling apps such as TextNow thinks that my phone is rooted and they can not run -- but my phone is not properly rooted according to root verification apps.
Please tell me how should I do the update to the latest version from this point and then I would like to unlock bootloader and install recovery and root it as well.
Please advice.
BTW my OP6T is global
Click to expand...
Click to collapse
Hello,
Here is a link that will help you out with this update process:
https://forum.xda-developers.com/oneplus-6t/how-to/official-oxygenos-9-0-4-ota-oneplus-6t-t3860953

a4abbas said:
I have OP6T OxygenOS 9.0.16 and I would like to update it to the latest 10.3.3 with root.
What should be my process of doing so? I have not been in touch with rooting for the past 3 years so I don't want to mess things up. Another note is that while I am on OxygenOS 9.0.16 I tried to root it which was failed, but now few banking and calling apps such as TextNow thinks that my phone is rooted and they can not run -- but my phone is not properly rooted according to root verification apps.
Please tell me how should I do the update to the latest version from this point and then I would like to unlock bootloader and install recovery and root it as well.
Please advice.
BTW my OP6T is global
Click to expand...
Click to collapse
Flash OOS full rom zip on both slots using TWRP also flash TWRP installer zip on both slots reboot recovery flash magisk reboot system. Easy peasy.
Example:
Boot recovery: fastboot boot twrp.img
flash OOS 10.3.3 full rom zip
flash TWRP installer zip, reboot recovery,
flash OOS 10.3.3 full rom zip, format data, wipe data,
flash TWRP installer zip
Reboot recovery, flash magisk,
reboot system.
Note: I use a USB stick. I flash magisk zip off my USB stick.
That's what I do when I use OOS on my 6t far as installation goes.
Edited

flash713 said:
Flash OOS full rom zip on both slots using TWRP also flash TWRP installer zip on both slots reboot recovery flash magisk reboot system. Easy peasy.
Example:
Boot recovery: fastboot boot twrp.img
flash OOS 10.3.3 full rom zip
flash TWRP installer zip, reboot recovery,
flash OOS 10.3.3 full rom zip, format data, wipe data,
flash TWRP installer zip
Reboot recovery, flash magisk,
reboot system.
Note: I use a USB stick. I flash magisk zip off my USB stick.
That's what I do when I use OOS on my 6t far as installation goes.
Edited
Click to expand...
Click to collapse
Are you sure there is no need to update to 9.0.17 and then 10.3.3?
I've asked once and someone said that 9.0.17 is neccessary before update to 10.3.x.
Also there is option to flash from system without losing magisk modules:
1. Flash manually from update center (do not reboot)
2. Enter magisk and flash to another slot (after OTA)
3. Flash TWRP installer like magisk module
4. Reboot
But I'm not sure if I remember it correctly.

Michalec said:
Are you sure there is no need to update to 9.0.17 and then 10.3.3?
I've asked once and someone said that 9.0.17 is neccessary before update to 10.3.x.
Also there is option to flash from system without losing magisk modules:
1. Flash manually from update center (do not reboot)
2. Enter magisk and flash to another slot (after OTA)
3. Flash TWRP installer like magisk module
4. Reboot
But I'm not sure if I remember it correctly.
Click to expand...
Click to collapse
10.3.3 is all that you need. 9.0.17 isn't the only way anymore.

Michalec said:
Are you sure there is no need to update to 9.0.17 and then 10.3.3?
I've asked once and someone said that 9.0.17 is neccessary before update to 10.3.x.
Also there is option to flash from system without losing magisk modules:
1. Flash manually from update center (do not reboot)
2. Enter magisk and flash to another slot (after OTA)
3. Flash TWRP installer like magisk module
4. Reboot
But I'm not sure if I remember it correctly.
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I have a T-Mobile SIM unlock OnePlus 6t and I converted it to an international model so when my conversation was done I was on OOS 9.0.1.1 and I booted TWRP and installed 10.3.4 full rom on both slots and also recovery installer and all just like my previous posts stated and everything went fine. I used mauronofrio's TWRP the version just before the latest 3.4xx when I did this.
I always download quite a bit of various firmwares and also TWRP versions before I start flashing things just in case something goes wrong I already have other things maybe I can use and I don't have to stop and wait for some download to finish... And I'm quite sure you know this but definitely make a backup of everything beforehand to USB or transfer it to your pc just in case you end up needing it as a precaution.
Edit added:
I am assuming that you already unlocked your bootloader... I believe everyone knows to do that that's on XDA forums before you can do anything to any device .. I say this after reading post below me here. I guess I should have said that earlier but I just assume everyone knows that on the forums... My bad. ??
From fastboot on Linux PC:
sudo fastboot oem unlock (then hit enter on keyboard) use volume keys to move to unlock option and your Power button to select it and confirm. For more info see: https://www.xda-developers.com/oneplus-6t-unlock-bootloader-root/
Super easy to unlock bootloader just remember it does wipe your device clean so move anything to want to PC or USB stick first...

I would think you could just update oxygenOS to latest then re-root no? Assuming your already bootloader unlocked which it seems like would be the case if you have an obsolete magisk installation.
Edit: re-reading your post maybe it is not unlocked as you failed to root. In this case just unlock then flash the latest fastboot image and then magisk as others have already stepped you through. You will lose data when you unlock so backup first.

So if I'm on 9.0.16 I could flash latest OOS directly from TWRP and then flash magisk? And no data loss? Of course I'm rooted with bootloader unlocked.

Oh dear this process is getting harder because recently I was busy doing other things it sounds way harder it actually is. Isnt there a way I pay someone on this forum so that user help me do this. Like download stuff links and proper version and follow me up with it because i want to do this without messing things up!

a4abbas said:
Oh dear this process is getting harder because recently I was busy doing other things it sounds way harder it actually is. Isnt there a way I pay someone on this forum so that user help me do this. Like download stuff links and proper version and follow me up with it because i want to do this without messing things up!
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It is indeed a tough job. This A/B partition has had a lot of people bootloop/soft bricked their phones.
However, you need not pay anybody anything. If you are on stock, I would've recommended you upgrading it via Oxygen updater (a 3rd party app on the play store) and then using the latest recoveries (TWRP 3.4) and flashing it via Fastboot mode.
It is super easy.