When Windows indexes the drive, yes, it will add folders and information. There may be other reasons but yes, it can do that.
Bob
I don't know why, but every time i plug in usb sticks or smartphone into my laptop or anything else, some folders are created which has a different shade than the normal folders. This folders are like system information, etc.Not just that, the folders in my computer, such as music folders, have the same problem as well. It creates smaller version of the original album art, for example.
My computer is Sony Vaio Pro 13 with windows 8.1 pro, model number SVP13218PGB. My antivirus is windows Defender (perhaps I need to get 3rd party antivirus?).

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