Up-dating - Refreshing the image navigator

Hi,

In my catalog, when I delete (Alt-Supp) a picture, that picture stay in the navigator but with "?" ("Hors ligne"). Same when I change the picture's name in the navigator, a "clone" of that picture appears with "?" ("Hors ligne")... 

That problem is new, it didn't occur before...

Could you help me ?

Thanks in advance