I am having this issue like for a week now. Happened when I tried to take a picture and a window told me that there was a problem with my external storage. My files on the sd card are there, gallery shows them up and I can play videos or access to every document. However I can not transfer files, move apps, or change it for my default storage place on camera. I've already unmounted it, shut down phone, removed it but the problem still there. I have a Class 10, 64GB Transcend card.
