Some PCs have internal speaker that can be used by Windows to produce beep sound. This was inherited from old systems when sound cards were not common place. Windows produces beep sound on many cases. One being when user presses enter key on a treeview control or an enter key on a textbox control. This is used to alert the user that the input is not acceptable for the control with the focus. But when you are using "SendKeys{System.Windows.Forms.Sendkeys}" to simulate keystrokes, this can get annoying. To disable this beep sound in Windows XP (should be applicable to Windows 7), open Device Manager (devmgmt.msc if you are cli buff). From the View menu, select Show hidden devices. See figure below. Figure 1. Show hidden devivces. Then drill down to Non-Plug and Play Driver/Beep, then open properties dialog. Figure 2. Traverse to the Beep device. From the dialog window, goto Drivers tab then click on "Stop" button. This should immediately disable the device...
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