Supression of Click Sound on WebBrowser Navigate

Open the Sounds and Multimedia Control Panel applet (go to Start, Settings, Control Panel, and double-click Sounds and Multimedia).
Select the Sounds tab.
Under Sound Events, navigate to the Internet Explorer section.
Navigate to Start Navigation and remove the sound for this event by selecting "none."
Click OK.

OR

Start the registry editor (e.g., regedit.exe).
Navigate to the HKEY_CURRENT_USER\AppEvents\Schemes\Apps\Explorer\Navigating subkey.
Select the .current subkey.
Select Delete from the Edit menu.
Click Yes in the confirmation dialog box.

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