[Galaxy Tab 10.1 Q&A, Help & Troubleshooting] REtails:
Hello!

I have a somewhat unusual challenge on my hand and am hoping there is a solution, however after days of searching I am unable to come up with a clear or consistent answer. I got a shiny new SM-T580 around the holidays, and immediately set to work on installing twrp, rooting the device, etc. to be able to use it for my needs. My device is OEM unlocked, rooted, has Xposed installed, and has a ton of hard to come by apps installed, as well as a substantial amount of important personal files on it. On Saturday, I went to flash a zip file to install a tool pertaining to ROM modification and the install unexpectedly failed because TWRP couldn't mount my /data partition; I realized I had completely forgotten to format /data after disabling encryption back when I first did everything, and my /data partition was still encrypted.

That being said, I really do need to remove the encryption, but I really need to preserve my data also. To make matters more complicated, I have enabled adoptable storage, and am using a 64gb card formatted as internal storage, with about ~30gb data on it. I have backed up my personal files to the cloud, but now am trying to figure out how to move my apps and app data. Ideally I would like to preserve my entire existing directory structure, as well as home screen configurations, etc. I am left with a few questions that are preventing me from proceeding:

How do I determine which data is stored on the actual external SD card? From my own poking around, it looks as though the external SD is /mnt/expand/aa11a11a-blah-blah-blah/ but I am not positive. If that is my SD card, can I simply move it to a new install? I assume the SD card is also encrypted, as I am guessing the string following /mnt/expand/ is an encrypted serial number or something of the sort. If that is the case, can I simply copy the files from the above directory, and then copy them back in after formatting the card? Beyond this, as far as what is actually stored on my phone, is there a means of backing up and restoring the files and directory structure and having it all still work and point to the right places? I don't know how the system links the adopted storage and just feel like I'm in over my head when it comes to understanding the nitty-gritty of Android file system internals. I would simply backup the whole partition and then restore it but then I would be back to square one with the encryption. I am competent with TWRP, ADB, ODIN, etc and would be very, very happy if anyone could point me in the right direction on this, even if the solution is complex. If I am unable to figure this out before the weekend I am going to have to manually back up all apps and click through 300+ apk files. I do also have titanium backup but I am kind of in a bind with storage space vs backup size. Anyhow, if you made it this far thank you so much for reading and I am looking forward to your replies! :highfive

Edit: This was intended for the Galaxy Tab A forum. Mods, please move this thread to Samsung Galaxy Tab A series Questions & Answers if possible, though the question should pertain to both device series on 6.0+. Thank you!