Win Media Player 10 and Creative Zen Sleek - Can't synch as MP3s anymore

When I first got my Creative Zen Sleek MP3 player, I couldn't get the included file management program to recognize the thing, so I instead used Windows Media Player 10 to synch my music to the player. It wouldn't immedately recognize the player upon starting; I'd have to refresh before it would find it. But it worked. Sort of. I soon discovered that it didn't synch them as MP3s, but rather as WMA files. Sure, they played just the same, but some songs just wouldn't convert, so I couldn't get them onto my Zen. It also didn't delete the converted files when it was done with them. Finally, the artist names were displayed in the synch window in an entirely random order (they showed up alphabetically on the Zen itself, though).

I was somehow (I have no idea how) able to fix all of these problems. All of a sudden, it would immediately find the player, display the artist names in alphabetical order, and most importantly, synch the MP3s as MP3s (and, thus, it was able to synch every song, even the ones it wouldn't before). The trouble is, I have no idea how I did it.

Now, a few days ago, I don't know what happened to my computer, but it caused a few minor problems, all of which that I had found, I soon fixed. Only an hour or so ago did I discover that Windows Media Player was corrupted. I was forced to reinstall Media Player, therefore undoing whatever I had done before, and so my original problems with my Zen have returned. I have no idea how to fix it again. I checked some of the settings in Media Player. I found a checkbox for whether or not to convert files. If it's deactivated, the files aren't converted, but they're also not playable; it just sends the files over to the Zen, it doesn't sort them into artist and album names as it should, and while they appear in Media Player and Windows Explorer, they won't appear on the Zen, and thus they can't be played. I tried manually adding the artist and album folders. Again, they only appear in Windows menus, not on the Zen menus. I tried restarting the computer with the Zen already attached and on, but there was no difference.

If anyone has any ideas, please, please for the love of Xenu, tell me. If any more information is necessary, I'll be glad to provide it as soon as possible.