Actually, that error could just mean that the sound card driver is broken.
But you can check the programs running using Task Manager.

What version of Windows?
http://zachd.com/pss/pss.html#dsound
is my general guide here...

-Zach
--
(speaking for myself and doing this in my free time)
See http://zachd.com/pss/pss.html for some helpful WMP info.
This posting is provided "AS IS" with no warranties, and confers no rights.
--

"alice" <alice@discussions.microsoft.com> wrote in message
news:8AE2BF07-AE23-474D-911C-D185E64DFA03@microsoft.com...
>I do not have sound on my computer, no default sounds, media player sound,
> just no sound on my computer. My media player visibly plays but no sound
> comes through. I don't get the sound alert for new email etc.. I have a
> working sound card & have updated sound card driver. When attempting to
> use
> media player, I get the following error message: "Another program is using
> the sound device, and preventing the Player from accessing it. Close all
> other programs so that the Player is the only program running, and then
> try
> to play the file again. "
>
> HOW do I determine what other program is using my sound. I don't have
> other
> progrmas opened. Some program is obviously 'using' my sound card but how
> do
> I find it?
>
> alice
>
>