How to Fix Windows System Sounds

Basic Fixes
1. Make sure the sound is not muted. To check the sound settings, double-click the speaker icon on the right side of the taskbar or go to the 'Start' menu, then select 'Control Panel' followed by 'Adjust system sounds' to open the volume mixer. If there is a button with a red circle that has a slash through it, the system is muted. Click on the button to make the red circle with the slash disappear and turn the sound back on.
2. Check the volume level in the volume mixer window. It is possible that the sound is working but that the volume is just too low for you to hear it. Turn the sound up by clicking the marker on the vertical scroll bar and moving it upward.
3. Find out if the sound card is correctly installed on the system. Click on the 'Start' menu, open the 'Control Panel,' choose 'Hardware and Sound' and then 'Device Manager.' The sound card should appear in the device list. If it does not, it is not installed correctly and should be reinstalled according to the instructions that came with your specific card.
K-Lite Codec Pack Fix
4. Download any version of the K-Lite Codec Pack from Codec Guide. K-Lite Codec Pack is a free application upgrade that contains the necessary codecs for your system to recognize different audio files and any of the versions contain the component that you need to fix your Windows system sounds.
5. Install the K-Lite Codec Pack on your system. During the on-screen installation process you can uncheck every component other than the Codec Tweak Tool, which is listed beneath the “Tools” header.
6. Go to the “Start” menu, then select “All Programs” > “K-Lite Codec Pack” > “Configuration” > “Codec Tweak Tool” to bring up the “Codec Tweak Tool – Select Options” screen.
7. Check the box next to “[Registry] Fix non-working system sounds” under “Fixes.” Also, make sure that “Detect broken codecs” is checked, which it should be by default. Click “Next” to continue to the next screen of the Codec Tweak Tool wizard.
8. Click the “OK” button to close the Codec Tweak Tool once the feature is finished running on your system. The Codec Tweak Tool wizard should find and the fix issues in the registry and on the sound card that are causing the Windows system sounds not to work.