Help getting Quicktime, Napster and WMP to work

I'm currently unable to:
1) download and install Quicktime (so I can't use iTunes)
2) play music in Napster
3) play music files in Windows Media Player

Is there an area on the computer that controls all this? The sound does work on my computer just fine. Whenever I try to do any of the above, each program basically gives me unknown errors.

I run avg on a daily basis. I also run Adaware and Spybot on a regular basis. I'm running WinXP Pro, SP2.

I've run every type of repair known to man to try to fix my Quicktime problem over the past 3 months. The napster stuff has just started happening about 2 weeks ago (could be because I must have "fiddled" with something important to fix the Quicktime problem).

Please help.

Cheryl.

 

I only use WMP. i would go to add remove delete WMP, it will do a roll back. then upgrade it if you want WMP 11. did you check to see if you had vonlume on mute? control panel-printers and other hardware-then on the left you will see sound-speech-audio-then sound and audio devices- there you can make sure it's not muted. and check other devices under hardware. GL