Your memory card might be infected with a shortcut virus when you plugged in the memory card and does not open the actual contents on the drive or see nothing...1st thing you need to do is to scan your card first with an antivirus program then try this software
First, you need to find a virus-kill program.
Then, you can recover images. Only few steps:
connect your phone to computer.
running the program
you can preview your photos and recover them