display properties

[steve.uk]

when i select display from the control panel and try to change my desktop
wallpaper, some of the original system wallpapers are not displayed in the
box below.

they are in the windows folder but not in the desktop option. one such item
is 'azul'.

if i right click the image and set it as desktop background it works fine
but if i browse from the desktop properties dialogue box then when i click
it nothing happens.

is there a way to repair the problem.

i have used sfc chkdsk blah blah blah, , ,

tx