Alright, I'm working on a presentation at work, and I'm looking at the Powerpoint slides the last guy who had my position used, and they all have a custom (i think) background (what Powerpoint calls "Slide Design"). I want to make a new Powerpoint presentation but I want to copy his Slide Design, but when I go go "apply a design template," the one that he used does not show up. Because it doesn't appear in the list, I assume it is custom. How do I locate custom Slide Designs on my computer? Is there a certain file extension I should search for?