[help] On Oreo, 8.1, latest, trying to install Magisk, and unable to install

[dmachine2]

I was following the guide at:
https://forum.xda-developers.com/pixel-xl/how-to/guide-pixel-xl-android-8-1oreo-unlock-t3715279

I started with a Pixel XL 7.2, unlocked, magisk, etc. I uninstalled magisk, updated all OTA updates, and then began the thread above.

I followed 6 - Extract boot.img from Fcatory Image and fastboot boot.img
The continued with 7 - Root with Magisk
booted to twrp, flashed twrp, no issues.
Rebooted to recovery, flashed elementalX kernel 3.04, and added magisk v16.3
No errors

Rebooted phone, and upon boot, got a message:
"there's an internal problem with your device"
From what I've read, that is not really an issue and has something to do with some things not matching, so, an update to magisk in the future will resolve it. So no big deal.
However, I don't see magisk manager, and have no root.

I reboot back to recovery, uninstall magisk manager, and reboot phone.
Still get the internal problem message, but no big deal.
I reboot back to recovery, and try flashing magisk again.
Still no manager, still no root (from root checker).

I try installing the magisk manager app directly, but, the APK cannot install, and just gives a generic error message of "app not installed".
Reboot to recovery, uninstall magisk again, wipe cache. Reboot, still same internal problem message.

Try to flash magisk 16.0 instead, repeat the above, and still no root, and can't install APK.

So, just kind of stuck at this point. Phone tells me that elementalx installed without an issue though, so, just seems like magisk is the last step. Any help is greatly appreciated. Thank you.

 

[noidea24]

The message you get upon boot is from the kernel, nothing to do with magisk. not that it matters, it doesnt affect anything.
According to EX thread and EX's official websites "How to install" guide, you are supposed to install magisk first. Thats how i do it.

what you need to do is......
Reflash the stock factory boot img and let it boot.
Reboot to bootloader flash or boot twrp, and install magisk.
Reboot let it boot all the way.
Then reboot to bootloader flash/boot twrp and install EX.
Reboot.

---------- Post added at 07:14 PM ---------- Previous post was at 07:12 PM ----------

Double post, sorry, butt.......

https://elementalx.org/how-to-install/
Read part one step three.
"3. Root your device (optional)
If you would like root access to your device, install SuperSU or Magisk. This should be done before installing ElementalX. Other root methods are NOT recommended. Root access will give you full control over your device and allow you to change kernel settings and tweak your device. To install SuperSU or Magisk, download to your device, reboot to recovery and install the zip you downloaded. Make sure you reboot into your system after the installation process completes. Ensure that root is correctly installed and working.

At this step, I usually make a backup of the stock rooted kernel. Now that you are rooted, you can do this very easily in EX Kernel Manager by selecting Tools->Kernel backup. This will save the boot.img."

 

[dmachine2]

Thank you for the help, will try it when I get a chance. The guide that I was following said for elementalx, flash kernel first. For exnoshadez, to do magisk first, for other kernels, do kernel first. I had read that some kernels need to go first, while others magisk needed to go first, and since that guide was specifically oreo, I thought kernel was first. But, thanks! Will try going back to factory boot image and progressing through.

 

[dmachine2]

So, I flashed back to stock boot.img, booted twrp, flashed twrp, and flashed magisk. But, Magisk still did not show up. I tried installing the magisk manager apk, but still get "App not installed" when trying that. At least the "there's an internal problem with your device" message went away.

Any other ideas on what to check when flashing, or why it's not "taking"?

Thanks again for the help.

 

[dmachine2]

Found out the problem:
Had to do:
adb uninstall com.topjohnwu.magisk
The key here was that I was upgrading from 7.2 to 8.1, and in the uninstall of magisk, I guess it left some remnant behind which prevented it from installing the new version.

The way I discovered this was trying to use adb to install the magisk manager apk, and that gave me the error:
adb: failed to install MagiskManager-v5.7.0.apk: Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE: Package com.topjohnwu.magisk signatures do not match the previously installed version; ignoring!]

Then, I simply uninstalled it, then flashed using twrp again, and it worked fine.