The source code schema for the WiX Toolset UI Extension. References a WixUI dialog set, either one that's included in WixToolset.UI.wixext or a custom dialog set included in your authoring. Extensibility point in the WiX XML Schema. Schema extensions can register additional elements at this point in the schema. Identifier for the dialog set to reference. An optional identifier that specifies the directory to set WIXUI_INSTALLDIR to, for WixUI dialog sets that require it. Enable checks to test whether the package is being installed to a network share or removable disk. The default is no. Extensibility point in the WiX XML Schema. Schema extensions can register additional attributes at this point in the schema.