The Windows 7 operating system allows you to customize the icons in the notification area on the taskbar. Along with the rest of the icons, the volume icon can be hidden or shown.
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Instructions
Step 1
To return the missing volume icon, right-click in an empty area of the taskbar and select Properties from the context menu.
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Step 2
In the "Taskbar and Start Menu Properties" window that opens, click the "Customize" button on the "Taskbar" tab.
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Step 3
In a new dialog box, you will see a list of icons that can appear in the notification area of the taskbar.
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Step 4
Find Volume in the list and select Show Icon and Notifications.
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Step 5
Check to see if the display of the system volume control icon is enabled by clicking the "Turn system icons on or off" link.
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Step 6
If the volume icon is disabled, enable it by selecting the appropriate value.