You have already inserted the memory SD card to your Galaxy S7 and the "For Transferring Photos and Media" Pop up notification is on your nerves? To fix SD card notification on Galaxy S7 and Galaxy S7 Edge, do one or all of these steps:
1. Make sure you have already created a backup of your data stored in the Memory Card, and then Format it by following this path: Settings > Storage > SD Card > Format.
2. Make sure to encrypt your memory SD Card. Go to Settings > Security
3. Make sure to give the Storage permission to the entire apps on your Galaxy S7. Go to Settings and search for Permissions and change the settings.
4. Make sure the SD card is completely fit in its slot, next to the SIM Card slot.
Note that, as far as we investigated, there is no certain way to fix this annoying mount and unmount (eject) SD card issue, and these steps have been reported to solve the problem for many users. The best solution to Fix SD card notification on Galaxy S7 (Edge) is to wait for Samsung to release an update, as Sprint has already issued and update.