Thanks for the reply.
I have installed at least two sets of codecs:
1) K-LITE Pack (Version 5.0.2)
2) Windows Essential Codec Pack [Version 2.3d (7-09)]
The reason I asked about the H.264 codec is that I'm also
using a "Plug-In" software for my Adobe Premier Elements version
4 (APE-4) which easily handles (loads)a FLV file for editing if
it has the H.263 codec, but NOT if the FLV has an H.264 codec.
For that (H.264)codec FLV file, I have to first use something
like Prism to convert the FLV to an AVI file and then load it
into APE-4 for editing.