[Karellen]

Now how I make Kodi to look for the artwork files again, I have renamed the folders and restarted Kodi but still I can't see any artwork for those sets.

Delete one of the movies in the set from your library. Rescrape it and Kodi will look for the set artwork again.

[ferdinand]

Thanks for all your help, now everything is working well.

[Klojum]

Thread marked solved.