Ahh, I think I know what it might be. Not sure if MediaLab still does this, but in v2004 it converted URLS to lowercase. I do not remember the rationale. This created an issue on some servers (e.g., Unix) which are case sensitive. If this is the issue, then a simple work-around would be to convert your actual URL path to lower case. In your case this would mean changing "Descriptions5" to "descriptions5". Can't promise anything but I think that would solve it.
PS., the copy of the post you saw via email doesn't appear here because I deleted and re-wrote it.