SD Card Mounting and dis mounting "SD Card stopped un expectedly" Is there a fix?

You're not the only one.

Now, you CAN do some checks though... Is your card a SanDisk one? Even 'better', is it 32GB? Maybe that's the culprit. SanDisk cards manufactured prior to December 2012 have a glitch in their chips that make them go bonkers with newer Samsung phones. If this is your case, you can have SanDisk issue an RMA and they'll get you a shiny, new card in the mail (just let them know it's the issue with Samsung phones, they know about it).

Or if you want to play it safe, get a Samsung card (expen$sive)
 
REALLLY? The answer is Yes and Yes. I will try finding a contact number for SanDisk Thanks for the info.