I can't tell how you are moving photos. In my LG G4 I have the Photo app save to the SD card directly so no moving. On my LG G4 open the camera app and click on the top left gear icon, then under the Gear will show internal or another icon that depicts the card. I use the card all the time and have for about a year.
I do NOT use CM and AVG optimizing suites in my phone. For me I found them to create trouble.
I just bought another SanDisk 32gig HD MicroSD card for my LG Optima phone, and the problem that broke my previous card has happened again... My card is fine for months, then suddenly, one morning I turn on my phone after charging it and attempt to move new photos or media from internal memory to my card, I get the following error message: Files cannot be moved due to an unknown error...
This is the second time this has occurred, making my card nearly useless, as I cannot put new data or media to the SD Card, nor can I transfer or delete any old files from the MicroSD card. I have removed the card from the phone, to check it with my computer...
My commostfilesQputer reads the card just as my phone does, and I can copy most files off the card without corrupting the data, but I cannot delete the files, nor reformat the card to make it usable for extra storrage again. The games, music, pictures and files are accessible whether on the phone or my PC... but can't be modified or deleted! What is causing this glitch, and how can I prevent another occurence. I have both CM and AVG optimizing sotware and security suites in my phone.

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