There are two versions of the Book.png and Book-32px.png icons (one is 'Book' and the other "BOOK"). According to Fridolyn Somers' post to koha-devel on 12/08/10, this causes problems with Windows files systems. At the view least, it's duplicating icons needlessly.
Created attachment 5384 [details] [review] Proposed Patch Removes duplicate Book and Book-32px icons, and updates database to use remaining file.
Created attachment 5670 [details] [review] Signed-off patch
Removes duplicate files, and updates the database to be sure any usage of the deleted files now points to the correct names. I'm the author of this, but I'm going to mark it as Passed QA unless anyone objects.
I have objections it is a clean and simple patch, pushing
Seems to work fine. Closing.