[CentOS] "General Error" in Firefox (CentOS 5.2) Video

This is a new instalation of CentOS 5.2
When I go to FireFox and try to watch a Video clip, some
files transfer, and then I get the message "General Error" in
the video window.

I ASSUME some additional software needs to be downloaded,
but what from where?

When running on that Other OS, a message comes up giving you
an opertunity to do the download.
-- 
                                        Reg.Clemens
                                        reg at dwf.com