Thanks for the reply! I had a couple of errors, one causing an extraneous 403 error..as you mentioned, incorrect filename (i.e. missing file). In addition, the file I need to access existed, but I did find a bug in my code where I thought I was properly waiting for the web request to complete before acting on the data. I had a button that should have been set as disabled until the data was ready, but it was active in Unity.