The screen of the clip reads: “Memory full. Connect to PC to delete more than 20M contents”, and won’t allow me to access it. When I connect to my PC it states that there is 24GB free (of 3.7MB). I’ve downloaded ONLY music: NO video, pictures, books, etc. Please explain.
Your player doesn’t actually have 24GB of internal storage, so probably the file system is corrupted. Right click on the drive, properties, tools, error checking -> Check now.
If it’s an option for you, you can probably go ahead and reformat it.