Why Does My Sound Say No Audio Output Device Installed When It Is Already Plugged In?

This problem may be due to hardware displacement or malfunctioning. In this situation the best thing is call a hardware expert to avoid any other damage. If your sound was working and just stopped today then you can do one of the following to correct the problem.

1. Un-plug the sound card from your computer and then plug it again into the slot.
2. Try to re-install driver of your sound card. Using the driver CD provided with your sound card could do this.
3. If you have installed any game or software recently and you are sure that this software or game may created the problem then try to un-install the game or software from your system.
4. Be sure that no one (other than you) use the computer because someone may have created the problem.
5. If the sound card still not working then try to use this sound card with other computer (or your friend's) to ensure its functionality.
6. If the card is working on other computer then you need to do something with your operating system otherwise you need to have a new sound card.

The above-mentioned points may be useful in solving your problem.