Android (HTC M8) has "forgotten" my SD Card is encrypted. Help!

[MistaVF]

Hi there,

Having a bit of a stressful problem. My HTC m8 (Marshmallow) is encrypted, as well as the external SD card. All my photos are on the SD card. I have lots backed up but I'm having a great trip to NYC that didn't backup to google because I was roaming (it seems). Anyway, today my phone crashed (I think the battery is failing, it turned off instantly at 14%). When it turned on, all my photos are showing a gray icon (like they are corrupted). I cannot imagine how every single photo (of thousands) in multiple folders has corrupted.

Now, I noticed that when I go into Storage options the "Encrypt SD Card" box is UNTICKED. Implying the phone has forgotten the card is encrypted and thus cannot read the images. Though I thought it was weird that it can read the directories at all, implying its doing a file by file encryption rather than a full card encryption.

Anyway, obviously I know my PIN number that I need to decrypt the phone at boot up, is there any tool I can use to decrypt the images using this PIN? My fear is that (upon some research) that this is "encFS" encryption, which uses an encfs6.xml file to read the data and consequently the crash has deleted/corrupted this file. If so, this seems like a very delicate encryption mechanism.

Anyway, please, anyone, help me get my photos back

Many Thanks

[MistaVF]

Actually, some of the settings etc have moved around. It's offering tips about scrolling etc.... has a new carrier update been rolled out? Has it wiped my SD card encryption file?

[hrym]

You should know if there's been an OS update as you'd have been prompted to install it.  Changes to the settings menu tend to suggest that, but it wouldn't happen silently.

There are companies that can recover lost or corrupted data, but they'll charge and that will be dependent on the complexity of the task.  It's difficult to diagnose something like this at a distance, but I'd say the most likely thing is that the file structure of the card has been corrupted.  If there was a write operation going on at the time the battery failed, this would be quite likely.  At this stage, I'd take the card out of the phone to prevent further damage.   If it's just the FAT, it may be recoverable, but only if you know what you're doing and only after taking an image copy of what's already there.  If the encryption file is there, but not in the index, the phone won't be able to see it and you don't want any part of it over-written.

This is, of course, an object lesson in why you should always keep backups!  Electronic storage is incredibly fragile and can fail at any time for any number of reasons.  I don't suppose you sync'd your photos with Dropbox or Google Photos, did you?