Desktop wallpaper corrupted behind Vista Sidebar

[Breeder]

I have a clean install of Vista Ultimate Edition 32 bit. I have a
strange problem where the desktop background is corrupted behind
Windows Sidebar as in the screenshot below:

http://img183.imageshack.us/my.php?i...1911339gc0.jpg


I never had this problem with my previous Vista install and I'm not
running anything new that should make any difference. The same Adobe
Gamma profiles on both monitors etc.


Any ideas anyone?


Many thanks!

[CrazyMonkey]

What happens when you change the background to an image?