|Hmm. What an odd situation, old thing...|
Autoplay.inf files generally just tell a computer to autoplay something on external media when it's plugged in - essentially, it's the thing that makes the installation menu on a CD-ROM, e.g., appear when you put them in the CD drive, without you having to navigate to the launcher in Windows Explorer. So, in this case, it opens (I assume) the media player's storage space, and you drag and drop files into there.
If that's the only problem you're having, it may be worth trying to reset the player and see what happens - that is, it may be the player rather than your computer. There should be a reset hole on the left side of the player. Poke it in with a pen nib until the player resets? If that doesn't work, you can reset it through recovery mode -if you bought it, I assume you have the software that came with it? If not, it's available for download, I think.