[Samsung Galaxy S 5 Unified Development] curiousrom:
Messed Up S5 G900V Install, Magisk v19.0 Fail & Adoptable Storage?

"...TWRP shows "External SD Card (0mb)" with two different micro SD cards." - Maybe you set your external SD card as Internal storage on first boot which may cause some problems like this one. See Micro SD Card as Internal Storage - Adoptable Storage.

When I installed Magisk on S5 G900M klte this is what I did: downloaded & copied to the external sdcard from the Magisk release thread: Latest Stable, Latest Uninstaller (it's TWRP flashable if something goes wrong) & Latest Magisk Manager.

Back into TWRP wiped both caches, then flashed Magisk-v18.1.zip & rebooted to System. Magisk Manager was not showing up so installed manually the MagiskManager....apk downloaded previously & everything was working fine.

"...BusyBox Pro wouldn't install because not rooted or something. Titanium Backup wouldn't backup/restore."- Before installing apps that requires root you have to check in Magisk Manager to see if everything is ok.

Many users reported problems with Titanium Backup for some apps because it did not backup/restored all the required libraries.

"...when I installed Magisk Manager-7.1.1-5b30c774 and it downloaded Magisk 19." - That's probably because in Magisk Manager > Settings you chose Update Channel: Beta instead of Stable.

Dozens of S5 LineageOS 16.0 users including me reported that Magisk v18.1 works fine so if it is not available in the XDA Magisk release thread then get it in https://github.com/topjohnwu/Magisk/releases and wait for S5 users' reports in this thread about a possible new v19.x version with the bugs fixed.

In TWRP MTP is enabled by default so as you can't boot to System because of the Magisk v19.0 on S5 bug & can't write to external SD card you could connect to PC & copy the latest Magisk uninstaller to the internal sdcard. Then disconnect the S5, flash it while still in TWRP & reboot to System

Maybe you will be able to connect to computer & retrieve some data from the external SD card. If not maybe some Migrate function from external SD card to internal sdcard is enabled as described in this post by [MENTION=3815580]rawdealer[/MENTION] with screenshots: https://xdaforums.com/showpost.php?p=69043222&postcount=4

I don't know if this becomes available in LineageOS 16.0 with the external SD card set as Internal storage, you tell me please.

After that in LineageOS stock Files explorer > navigate to the external SD card > 3-dots > Storage settings > use Format instead of Format as internal which will format the card with the vfat FAT32 file system which the S5 likes. All the data on the external SD card will be erased! A notification will ask what you want to do with the SD card: choose Portable storage obviously.

Or turn off the S5, remove the card & format it in a computer.

I never tried to format the card while in TWRP. In either case choose vfat FAT32 or exFAT.

Copy to external Micro SD Card the LineageOS firmware, Open GApps ARM 9.0 Pico & Magisk Latest Stable, Latest Uninstaller (it's TWRP flashable if something goes wrong) & Latest Magisk Manager.

I prefer the smaller Pico package.

Reboot in TWRP & do a clean install: > Wipe > Advanced Wipe > wipe System, Data, the Dalvik / Art cache & Cache.

I would recommend: flash the LineageOS firmware + GApps, then reboot to system then back in TWRP & do an other backup of the clean install you just did before installing Magisk.

Or do a S5 super clean install (with Format Data instead of just wipe).

Please report back if you fixed your problems or not. :cool:

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