Windows 7: Music Library does not show album art in 'Artist' view.

This applies only to Windows Explorer and only in 'Artist' view:



This is 'Album' view in Explorer:





All album artwork was appearing in WMP, but in order to resolve this problem I readded my music directory to my library. Now all of it is being refreshed in WMP but it doesn't seem to make a difference in 'Artist' view for Explorer.

I bought a new computer with Windows 8 and I transferred all of my music over. Though I have set it all up thoroughly in both WMP and iTunes, opening my music library and arranging by artist, album, song, genre, or rating does not generate thumbnails. It seems that Windows is aware of the number of contents (for example, for an artist with two albums, two generic album thumbnails appear for the artist). Only arranging by folder shows actual graphics.