Why do I get a "Some components are not available" error when trying to play a clip in RealPlayer?

If you receive the message "Some components are not available to provide playback of this presentation on your system," RealPlayer has recognized the file you accessed, but the playback software for this file does not exist on your computer. By default, RealPlayer can play RealMedia and MPEG files. Note for Mac users: The RealAudio 3 file format is no longer supported.
 
RealPlayer can play almost any other media type if the appropriate plug-in and codec (compression/decompression system) are installed on your computer.

To install the components required for your system to recognize other types of files, click here for instructions.