Windows Volume control is uninstalled by incident. Then search and find the following methods to recover it, in cmd line, excute the 2 commands as below:
expand c:i386sndvol32.ex_ c:windowssystem32dllcachesndvol32.exe
expand c:i386sndvol32.ex_ c:windowssystem32sndvol32.exe
c:i386 is the directory you recover point.[@more@]