Media file could not be played since the file is missing or is not in the correct format. Media file: %1 culture: %2 Cause: ...

Media file could not be played since the file is missing or is not in the correct format.

Media file: %1 culture: %2
Cause: Media file is missing or is not in the correct format. This may be a result of a user dialing in to the  Conferencing Attendant from a different pool and selecting a language that is unsupported in this pool.
Resolution:
Verify that the media files for Conferencing Announcement Service have been installed in the correct folder and use a supported file format. If the user joined the conference from a different pool, verify that the Conferencing Announcement Service in this pool supports the same languages as the other pool.