When I Figured Out the Issue

There I was, ready to fire off an email to a developer about a bug (or so I thought it was a bug) in his macro when I figured it out on my own. You see, I ran MP3FileLister.xls over a directory with 1065 MP3 files. The macro stopped after processing 124 MP3s and displayed:

I clicked Debug and saw this:

It was confusing how the macro processed some of the files, but then stated that the file wasn’t found. 

I went to my directory and looked for what would be the 125th file. The filename had odd characters in it so I renamed that file and reran the process - it worked!