Basic Customization > Windchill Customization Basics > Managing Customizations > Best Practices for Customizing Files Supplied by PTC > Managing codebase Property Files > Manipulating Property Files > Using XCONF Files
  
Using XCONF Files
The XCONF files supplied by PTC are not intended for direct editing. All *.xconf files, except <Windchill>/declarations.xconf and <Windchill>/site.xconf should be considered read-only. The declarations.xconf and site.xconf files are both manipulated by the xconfmanager Utility. See Using the xconfmanager Utility for details on using the xconfmanager Utility.