If you want to use the Samsung Galaxy S7 with a memory card, it is recommended that you format it before the first use Android marshmallow. Only in this way it is ensured that the memory card uses the correct file system and you can use it fully in your new smartphone.
We tell you how to format the micro SD memory card in the Samsung Galaxy S7:
Warning! When formatting the memory card all data located on it will be erased. Make a backup of your memory card data!
1. Now open from the start screen of the Samsung Galaxy S7 the menu and then the Settings.
2. Scroll down a bit to "memory" and tap the menu item.
3. Continue to "SD card"
4. In this menu you can now see the "Format" option. Select this and follow the wizard.
Then your memory card with the appropriate file system for the Samsung Galaxy S7 has been formatted. The Micro SD card can now be used as desired.