Thread: Default Beep Event Missing

After finishing the installation of Norton Anti-Virus 2005, the event "Default Beep" vanished from the Sound Scheme portion of the Sounds option which is in the Control Panel on one of my PCs. I also knew that there is a problem in registry and I once knew that how to fix it as it happened my PC, but I need to refresh it. Any help out there?
Thanks...

Though this is good advice, but i am also encountered with a similar issue where it seems all the windows schemes are been corrupted. I have regular sound within which games, playing of mp3's and or software program sounds, but the "windows" default sound schemes are been disabled. For example: default the volume icon by ding it now and then the default computer speaker tone or the startup and shutdown sounds which are missing completely. The only two new programs I have installed is "Goldwave" sound editor and Daemon Tools"---image drive. Thinking that this may be the problem I promptly uninstalled these programs but the problem still exists in the computer.