HTC 10 SD card unmounting - critical data loss imminent!

[AC Question]

Hi guys, I have read online that one of the common issues with HTC 10 is the self-unmounting of the SD card. Unfortunately, mine is formatted as internal memory and encrypted. Yes, double whammy.

Facts:

1. My SD card unmounts itself after about 60-90 seconds of rebooting
2. It sometimes mounts itself again but usually I have to reboot the phone
3. I have some invaluable family videos/photos that I would like to transfer but the memory card doesn't remain mounted long enough for me to do anything
4. My Mac does not recognise the SD card when inserted on its own, because of the encryption I guess
5. I am currently on Android 6.0.1 and software number is 1.95.401.4
6. My set indicates a software update available (2.41.401.3) around 1.17 GB but every time I try to download it I get this message:

"Your phone storage is not available to store the system software update because it is being used by your PC as USB storage. Disconnect USB and press OK yo start the download, or press Cancel to exit."

This happens even when the phone is not connected to the PC/Mac so I am guessing its got something to do with the SD card being unmounted.

7. Any chance of this SD card issue going away after the update?
8. Is there a way to update the phone offline?
9. Is this a hardware or software issue?

I really need help here guys, I'm not sure what my options are at this point but I would really, really like to get access to my family media. Any help would be greatly appreciated.

HTC 10
SanDisk 128GB microSD card

 

[B. Diddy]

Welcome to Android Central! Hmm, that's a real dilemma.:-\ My guess is that the card itself might be corrupt, although the SD reader on the phone might also be faulty (or perhaps the contacts are dirty). Try Unmounting the card (in Settings>Storage), removing it, then using a can of compressed air to blow out the SD slot.

I can't think of a good way to back up that data if the card constantly unmounts. And you're right, other devices won't be able to read it, since it's encrypted by your phone (so only your phone can read it). In the future, to avoid this kind of mishap, I would strongly recommend taking advantage of Google Photos auto backup: https://support.google.com/photos/answer/6193313?co=GENIE.Platform=Android&hl=en