If your Windows Taskbar Volume Control icon has stopped working, and when you click on the volume icon nothing happens and you are not able to change the volume then this post has some working ...

The key usually falls within the Function keys on the keyboard. Click on the Volume icon on the taskbar notification area. Click on the chevron (upward pointing arrow head) above the master volume ...

An area on the right side of the Taskbar on the Windows interface used to display the status of various functions, such as speaker volume and modem ... an application icon in the System Tray ...