It could also be the name of your index-file.
I think httpd.conf default is index.html and since httpd.conf is set to not allow browsing of directories, this could be why you get the error-message.
Either change the name of your index-file, or change the default name for the index-file in httpd.conf.
[Edit: Since the forum reports that this topic has 0 replies I thought I'd try to edit just to see if it updated]
//megus