I just tried using my USB flash drive on my Android Device via USB-OTG, and it worked great. However, I tried re-connecting the drive to a computer, and these strangely-named files appeared. They are undeletable via both Windows Explorer AND command prompt, and I'm not quite sure if they are malicious. I can access the rest of the files on the drive normally, but I can't move, copy, or delete the files in question from the drive. What are these files, and are they a necessary part of the drive?