Card corrupted??

Hi, wonder if you could help me out here…

I am using Extreme SD XCI. 45MB/s. 64GB.

I open it on a MacBook Air with Mac’s inbuilt card reader. 

Before this no problem except one time it took forever to open the files and I lost the files in the end. 

But after that with further shootings there was no issue. 

And then it happened again today, after 8 hours of shooting on Nikon D7000 camera, 

Problem today: towards the end of the shooting, I realized I could not view the files I had on my camera anymore. 

I tried to open in MacBook Air. No hope. It says the card is not readable. 

But it was able to read the very same card last night!

Could you help let me know how I can recover my files in the card?

Thanks very much for your advice. 

Niabail

Oh, guy! You suffered from the same thing which ever trouble me. I don’t know why SanDisk is so easy to corrupted in camera. I have tried to use the recovery tool provided  by SanDisk, but it didn’t work. So I tried to find other option on the web. Finally, I got a tool which helped me recover SanDisk memory card on Mac. You can know more here: tips for SanDisk memory card on Mac.