Invisible SD

[iaintx]

I broke my Moto G7 a few weeks back, and Project FI replaced it under the damaged equipment plan, so I've had a new G7 for about three weeks now.

When I got my first G7, I formatted a Samsung SD card as internal, moved most of my apps to it, and used it for my music collection. It was visible as External in file management apps and when I selected USB file transfer.

Since I replaced that phone, I've had the SD card in the new one, transferred apps to it and it worked fine. But today I tried to copy music to it via USB, and there was no external SD. Solid Explorer and Amaze both no longer see any external storage. But I can still move apps to external and back, either manually or using AppManager III, which certainly recognizes the external drive.

I've spent a lot of time today googling, and the best I can find is cache problems with older versions of Android affecting USB, or the external drive vanishing completely, which isn't the case for me, since I can still move apps. By the same token, it seems unlikely to be a problem specific to this phone, since the drive's being recognized.

Any ideas what might be going on?

 

[B. Diddy]

Welcome to Android Central! Are you saying that you're using the same SD card in the new phone that you had in the old phone? If you formatted the card as Internal Storage, it shouldn't work in a different phone, since it would've been encrypted to the first phone. If you can use the card in the new phone, then I would think that it actually was formatted as Portable Storage.

Another thing to keep in mind is that Moto has a history of wonky implementation of Adoptable Storage. We've seen posts here about people who have formatted a card as Internal Storage, and yet the phone keeps giving a low storage error despite the card having a ton of free space.

 

[Mooncatt]

I agree with B. Diddy that this could be due to an adoptable storage implementation issue (and one of the reasons it's not a recommended option in the first place). On the off chance the phone is handling it correctly, have you made sure you are transferring correctly by switching to MTP mode from the notification bar when plugging into the computer? Often times the phone will default to USB charging mode, which would prevent the computer from seeing the storage and unable to transfer files.

 

[iaintx]

Thanks for the replies. I'm fairly sure that the card is set up correctly, though I don't understand Adoptable Storage. Let me go through what I've done to be sure I have the card correctly formatted:

* When I got the new phone, I immediately reformatted the card.
* Yesterday, when I noticed that it wasn't appearing, I moved all applications to internal from external, unmounted the card and rebooted.
* When that didn't work, I reformatted the card as "portable", then reformatted it to internal so that it shouldn't have remembered anything about the card.
* When that didn't work, I unmounted the card again, removed it, went to the storage manager and "forgot" the SD card, then
* Reinserted the card and reformatted (it wasn't recognized at all)

So I'm confident that the card isn't formatted as portable (if it was, wouldn't it show in file managers / USB anyway? I didn't think to check that when I did have it formatted as portable) and that there's no cache problems with apps or data being left around on the SD card.

I'm definitely switching the phone to file transfer on notifications. I enabled developer mode when I first got the phone, and I've toggled it between all options to try to make the SD card appear.

I just skimmed a link on Adoptable Storage, and I see why it's necessary to reformat every time.

I'm still most puzzled about the OS and AppManager being able to move between the drives cleanly, while it doesn't show up at all in the file management utilities I've tried. That would be independent of whether or not I screwed up the USB connection.

 

[B. Diddy]

It sounds like the last thing you did was to format it as Internal before you unmounted it and "forgot" it. So now you're inserting a card that's encrypted, and you may have told the phone to forget the encryption key. Can you reformat the card in your computer?

 

[iaintx]

I can certainly try it. Wouldn't reformatting it have given it a new encryption key, though?

 

[B. Diddy]

Sorry, can you clarify -- when you last reinserted it and reformatted, you said it wasn't recognized at all. Do you mean it wasn't recognized when you first reinserted it, or after you reformatted it?

 

[iaintx]

No, it wasn't recognized when I inserted it, but it was fine after reformatting, which is what I'd expect.

I just unmounted/forgot it and stuck it into my notebook. Windows wouldn't recognize it, of course, and there were two partitions, so I deleted both and reformatted as FAT32, which I figure should be as close to a brand new card as I can get. Reinserted, Android recognized it as a portable drive. Reformatted as internal, same issue as always. Android's happy to move my apps to it, but it's invisible to file managers and USB.

 

[B. Diddy]

When you format the card as Internal Storage, the phone regards it as part of its own Internal Storage, and is no longer regarded as an external SD card. So it wouldn't show up in a file manager as an external SD card. Did you try looking in the Internal Storage? Also, are you certain that you had formatted the card as Internal Storage with your previous G7?

This might still boil down to wonky implementation of Adoptable Storage by Moto.:-\

 

[iaintx]

I'm starting to doubt my sanity here. I'm absolutely sure I had the card formatted as internal storage, because I had apps and music on it, and the automatic app relocation and rebuilding the music lists only happens on internal storage. Just like I've done on my Galaxy tablet for years. Except I just checked the tablet, and its SD card is formatted as portable storage.

So yeah, I'm certain I remember how I had the other phone set up, but no longer as certain as I was...

So if the SD card has become part of the filesystem heirarchy, how do I find where it's located, so that I can move music to it, either with a file manager or with USB?

 

[B. Diddy]

Samsung devices have never supported Adoptable Storage (I think because Samsung either didn't trust the reliability of Adoptable Storage, or just didn't want to bother implementing it), so on your tablet, you must have been using the "Move to SD" option. It probably also had an option in the system settings to use the SD card as the default storage location, which means that any app that could use the SD card for data storage (not installation) would use it, and any file downloads would go to the card. But when you installed an app, it would still have to download to Internal Storage and install there (and then a portion of the app could then be "moved to SD," but only a portion).

The way Adoptable Storage is supposed to work, the card is supposed to be completely integrated into the system's Internal Storage, so you wouldn't be able to distinguish between Internal and SD using a file manager. The idea is that you'd just install apps and save music on the device, and the system would decide where it goes. This article has some interesting information, but doesn't say anything specifically about how file managers treat the two locations: https://source.android.com/devices/storage/adoptable

Admittedly, I haven't personally experimented with Adoptable Storage since I primarily use devices that don't support it (i.e., Pixels). However, I do have a Lenovo Tab 4 8", which does support it, so maybe I'll fiddle around with it.

 

[iaintx]

OK. I think I understand it much better now, and I appreciate the corrections from both of you. I think either the adoptable storage wasn't working correctly on my last phone (there have been a couple of updates since then) or I am simply wrong that I formatted the drive as internal. I'm not convinced either way, but I'm certain that you're right in that it's working correctly now.

The final thing that convinces me is that I have made a point of not moving Audible to the SD card, because I rely on the widget, and it didn't work on the SD card. Now it's moved to the new version, and the widget is fine, so my new adoptable storage is different from what I was using prior to the break.

However - now it leaves me with a problem. When I move all of my music to the music folder, it uses up most of the normal storage. So I'm back with the problem I was initially trying to solve. The adoptable storage appears to have a magic relinking mechanism to make the location of files invisible to apps that are aware of it, but I don't see a way to use it for large amounts of data. Since the SD card is 256 gigabytes, it seems a waste not to be able to move my data to it while the primary drive is almost full.