I'm running Windows 7 Pro on a Dell Inspiron 1720. I have desktop slideshow enabled and pointed to a folder of my favourite pictures. Occasionally I will force a switch to the next picture from the desktop context menu item "Next desktop background" which appears between the "NVIDIA control panel" and "New" menu items. However, every now and then this menu item disappears and the only way to get it back is to go into the desktop settings (Personalize) and reselect "Desktop Background" and reselect the picture folder. This is very annoying. Does anyone know why this would happen (three times in the last hour)?