Hi,
It seems to be a problem with TWRP without wipe - I already posted in their thread but nobody answered yet.
I also tried some more times to install it and always the same problem - so I'd have 2 questions:
1.: Did you also OTA from BTU (MM) or did you flash Nougat Beta 1 and did an OTA to ZPLN? (well same result if I flash Beta 1 and OTA to Beta 5 and flash TWRP)
2.: Will I be able to get OTA if I factory reset, flash TWRP without booting to system and flashing root + devbase or does it have the same effect like enabling modifications at startup of TWRP?
Regards,
Nestade
1. To be honest I have flashed latest "dumped" Nougat beta. Personally I'm not in "beta program" so can't perform OTA in my phone
"Supposedly" it was 100% clean, but just noticed it isn't...
If you are 100% sure that you never swiped "Allow system modifications" in TWRP in your current system and never remounted it rw (*) - you can help me to re-produce your issue with rooting latest nougat beta (and find a workaround, if possible).
(*) you can check if you have untouched /system partition by re-flashing ZPLN Stock recovery (from
HERE). Flash it, then enter it and see if there is "dm-verity error..." message (or not) at the bottom.
If you do NOT have such error message then GREAT

please provide me exact dump of your /system partition (use Terminal Emulator from Play Store):
Code:
su
dd bs=4096 if=/dev/block/sda14 of=/data/media/0/system.img
Copy above file to your PC (it will be located in internal memory -> AKA emulated sdcard). Copy also your original (backed up by SuperSU installer) stock kernel - you can find it in both places - /cache and /data (it is named "stock_boot_****.tar.gz, where **** is SHA1 sum). Compress all files using zip or 7zip and give me DL link, please
2. Probably your device will not be able to boot (without wipe) if you unroot non-encrypted device but I'm not 100% sure (I never decrypted my /data @ G935F, yet...)