I had this problem since I bought my Samsung A7 2017, using a Samsung micro SD card EVO 128 GB. I have tried all the suggestions in this forum and other sources. But I finally got it to work myself!!!. First let me show what I tried before I fixed the problem:
- Re-formatted the card from the device
- Re-formatted the card from Windows 7
- Re-inserted the card to the slot correctly (see this
https://youtu.be/KEsFHnuGWms)
Facts:
- I didn't want to block the UI notification, this would be only a workaround, would not fix the problem itself.
- I have already used the same card on another device (S5) and never had this problem, so I was sure that the card was ok.
After 1 week of lot of tries and annoying notifications, card unmounting, etc. I noticed my card had a small golden sticker on the same side of the contacts. This is a guarantee that the card was a genuine Samsung product. However, I suspected that, although the sticker was tiny, it could affect the contact inside the device. So I took an extreme measure and removed that sticker. Voilá!!! After that, no more notifications whatsoever.
Hope this helps.
Cheers,
Helder