Clipart Problem

[ArmorOfGod]

I have clipart in my computer that looks fine when I open the folder it is in, but when I click on it to alter or just view it, it changes the area behind the image black. When I try to insert cliparts like that into documents, it is the image, but it is in a black box.
Why do some of my cliparts do that? The majority of the pieces I have go into documents and look fine.

AoG