[Scott Jensen] "http://www.mywebsite.com/photofolder"
Probably the last forward slash. Depending on the server it may or may not interpret this as a folder and may or may not show you the folder contents if there is no index file.
http://www.mywebsite.com/photofolder/
Generally - the first thing the server will do when you put in this address is look for an index file in the folder. If one is there it will execute the index file. If not, based on the configuration, it will either give you a 404 or show you the folder contents.
Abraham