Can't set Vista wallpaper/no picture thumbnails

My daughter's laptop (Vista 32-bit) was running slow but no obvious signs of virus. I ran Advanced System Care (quick scan first, then complete) and it is back to normal speed... she's very happy!

However, one problem still exists: she can't set a picture as her wallpaper. Also, pictures don't preview as thumbnails; she just has a blurry picture icon instead.

In Folder Options/View, "Always show icons, never thumbnails" is unchecked so that isn't it. Is there possibly a file association error?

Thanks in advance for any help or advice you can give me!

 

More details about what happens when she follows this http://windows.microsoft.com/en-us/windows-vista/change-your-desktop-background-wallpaper

Note: I don't run Vista but I do have Win 7 installed and changing desktop is similar in Vista and 7.

 

Thanks but that doesn't work. I found out that the "Show window previews (thumbnails)" selection when you right-click on the taskbar is greyed out... it won't let me select it. I think that's the key to everything.

And I've tried everything I could find on the web... edit registry, check to make sure processes are running, aero enabled, etc... no luck.

Any other ideas?

 

You need to click on View or Views, on Windows Explorer window Menu bar, and have it set to either Medium Icons, Large Icons, or Extra Large Icons to see a thumbnail preview of the file image as the icon.

If thumbnails will still not show on the file icon even with thumbnails turned on, then check to make sure that Windows Photo Gallery is set as the default program.
http://www.vistax64.com/tutorials/83196-default-programs-program-default-associations.html

 

Thanks a lot but neither worked When I went to set Windows Photo Gallery as the default viewer I had no choice... there were all selected but greyed out, I couldn't change any settings.