Whole folder disappeared, it's not hidden

Hello,
I have a problem. a whole folder disappeared from my D partition (pictures, music, games), and I checked it's not hidden. even did system restore and still the folder and the contents didn't showed up. the memory card shows same amount of memory space used, and that's how I know that the files must be still here. I don't know what kind of treat or malware or virus came into my pc, I've scanned it, it didn't showed anything. please help me. thank you

p.s I ran cmd, and found folder $recycle.bin with the amount of memory that i've lost, but when i open it it still doesn't show anything.

p.p.s i haven't delete the folder.