Windows XPS 400

click my computer, click control panel, click display, click the themes tab, the settings to turn off themes are located here.
click my computer, click control panel, click sounds and audio devices, click the sounds tab, look in the sound scheme, select: "no sounds", click apply, close all windows, restart computer.

when I hve followed this plan and hit no sounds and then hit OK, a message comes up reading you cannot choose no sounds as a sound scheme.

Actually I hit save as and the message came up you cannot choose no sounds as a sound scheme. Thanks to your note this time in place of hitting save as, ok was applied and the computer was turned off and on again with no sound.
Thank You