Artist thumbs

I thought this may have been a skin issue, but have tried others with the same result.
The issue I have is that in Library mode, some of the artist thumbs refuse to show up when browsing my music library.
Some of them show up, so I guess that means that they're somewhere in the userdata folder, but if the thumb doesn't exist there then shouldn't it look elsewhere to find them? It's my understanding that if there is a folder.jpg in the artist root menu, then this xbmc should eventually look in this folder for them right?

Please help me out here guys, it's driving me a bit nuts.

While folder.jpg is the key to getting covers, they have to be in same folder of the music played, not a level or two up. XBMC doesn't go sniffing around for misc folder jpegs and assign them correctly.

For artist thumbs, we use the common path of all music files by that artist. So if you use <artist>/<album>/song.mp3 then you'd put them in the <artist> folder.

Well, that's exactly where I currently have them. My folder structure looks like this;

/ Music
/folder.jpg
/fanart.jpg
/logo.png
// Artist
/// Album
///folder.jpg
///cdart.png

So, by what you're saying there shouldn't be any reason for them not to show up. But they don't.

Right, I've read through all I can on the wiki, and I just can't find a solution to this.
After deleting all the music thumbnails in the userdata folder, nothing shows up. Despite all the album art, cd art, fan art and thumbnails existing where they should do in their respective folders inside the main music folder structure.

I've run the update, cleaned the library etc.

What the hell am I doing wrong

You've deleted cached information and now have stale information in the database. Delete the database so you're starting fresh.

Then rescan.

Based on your filesystem above, the folder.jpg/fanart.jpg needs to be inside the Artist folder.

Thanks jmarshall. I deleted the Mymusic18.db file from the userdata folder, but some thumbs still show up which aren't there.
Is there somewhere else that they are still stored?
Thanks.