We’ve narrowed it down to the JRunScripts Virtual directory that we had to add. He had created the virtual directory, but he had overlooked unchecking “Read” access, clicking the “Remove” button next to the application name, and selecting “Scripts and Executables” for Execute Permissions. I’m guessing it’s the Execute permissions that needed to be switched from “Scripts” that fixed the problem, but now at least I’ll know for future reference if this happens again.