If you have installed Windows XP OS in "control Panel", expand the "Sounds and audio devices". Check the box "Show icon..." and confirm the selection by pressing OK. If the checkbox is checked, uncheck it and click OK. Then again put the flag in the checkbox and confirm by pressing OK.
If you try to select a system message "you Have not installed the program...", from start run search bar and type the name of the file sndvol32.exe. It should be in the folder C:Windowssystem32. If not have this file, copy it on another computer or on your installation CD and place it into the correct folder.
If the item is inactive (overexposed), just call the line to "Open" a combination of Win+R and type regedit. Find the section HKEY_CURRENT_USERSoftwareMicrosoftwindowscurrentversionappletssystray. Set the value of the Services parameter to dword:0000001f. To remove the icon of the sound of the tray into the category of "Value" type 0000001b.
To solve the problem in Windows Vista and Windows 7, right-click Unallocated space on the "taskbar" and select the "Properties" command in the drop-down menu. Click "Configure" and select the list item "Volume". Set to "Show icon and notifications" and click on "Enable or disable system icons" to check the result.
If inactive, call the registry editor by command regedit. In section HKEY_CURRENT_USERSoftwareMicrosoftwindowscurrentversionexplorertraynotify delete keys IconStreams and PastIconsStream.
Right click the mouse on the icon "My computer" call drop-down menu and select the option "Manage". Expand the snap-in "Services and applications". In the Services snap-in, locate the "Node universal PnP devices". Call the context menu right click the mouse, select "Properties" and set "startup Type Automatic".