"A Surface is Using a Texture That Can't be Found" Message

[larq]

I have done a search of my computer for the two files in questions and come up emptyhanded. I presume that means that they have been removed. How do I go about finding the textures associated with those two files? I have dozens of textures in my drawing.

I thought to go check in the recyle bin and found my two files there. I restored them and no longer get the message when opening 3D. I don't know what objects these textures are on.

They came originally from photographs that I took and imported and then discarded because I didn't need them. I don't recall using them. Is there a way to find these objects? I have other files of this type that I was waiting to clean up when I finished my design. Perhaps I should just leave them all be?