If you have sourced the publishing
point from a directory, you have the option of
announcing either a single file or all of the files in the
directory.
A file in the directory. Click this option to create an
announcement file that directs Windows Media Player to connect to
the file specified in the text box. Type the name of the file or
click Browse to locate it.
All files in the directory. Click this option to create
an announcement file that directs Windows Media Player to connect
to the publishing point using a wildcard character. This causes all
of the files in the directory to be streamed to the Player. To use
this option, you must enable the Enable access to directory
content using wildcards property on the Properties tab
of the publishing point.