Windows 10 desktop slideshow

My lovely husband has a new laptop running Windows 10, but there's a problem. He wants the desktop background/wallpaper to show a slideshow of all the pictures he has in his Pictures library. He has selected Pictures" as the folder to use as a basis of the slideshow, but his computer will only show pictures which are directly in that Pictures folder, and not organised into other folders within the Pictures folder.

He has all his pictures organised into subfolders within the Pictures folder, so nothing now appears on his desktop background.

I know it worked on his previous laptop, which also ran Windows 10, and I can't find anywhere I can select "include subfolders" or something like that. How can we make this work?

(I've tried to set this up on my new laptop too, and it does the same thing, so I wonder if it's something to do with the current version of Windows 10.)

I've seen advice online to set up a pictures folder called Slideshow and copy all pictures into there, but it seems silly to me to have to have duplicates of everything, especially when I know this did used to work on his last laptop.

Thanks, stephen. But that only lets me select one single folder of pictures to include from within the main Pictures folder, which is not what we're trying to do. We would like the entire contents of the Pictures folder--so, the contents of ALL the folders within it--to be included in the slideshow. It's how we both had our previous laptops set up, and they were both running Windows 10 too.

Stephan, will reinstalling Photo Viewer, as explained in that link, sort out my issue? Or are you just suggesting I do it because it is a better photo viewer than the newer option?

Thanks, Matera. I've gone through the steps there and it only allows me to select the few pictures which aren't in subfolders and, oddly, one of the subfolders. That's all. I've tried all sorts of things and can't get it to do anything else. Bah.