SPWebApplication.AllowSilverlightPrompt Property
SharePoint 2010
Gets or sets a value that indicates whether UI elements that use Microsoft Silverlight to render should prompt the user to download the Silverlight application.
Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
Available in Sandboxed Solutions: No
Property Value
Type: System.Booleantrue to specify that the user be prompted to download Silverlight; otherwise, false. By default, this property is set to true.