Ok, you missed the point of my question. I understand how the file attachment module is supposed to work.

Gross lack of detail is the root problem. I do not understand what one means when they say, "does not show up".
Like it never uploaded?
Like it uploaded but no file is on the server?
Are you trying this from a different browser?
Any error messages?
What does the operator see? Does he think it uploaded ok?
Is it only the customer than cannot see the file uploaded by the operator?
Have you looked in the attachments directory on the server to see if the file is there?
How big is the file?
What type of file? PDF, DOC, etc?