A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
Here's a trick I learned at the 2018 Presentation Summit from Troy Chollar, who described this very problem. He said that you should find the subfolder that contains the textures for the model you imported. Remove all of the textures from the subfolder and put them in the main folder that contains the model. Then re-import the model into PowerPoint. This solution was for 3D models downloaded from third-party 3D model vendors, which typically are ZIP files that contains all of the assets. If you created the texture file separately from the 3D model in Photoshop, then placing that file in the same folder as your OBJ file might work.