You can change resources from within the Workbench or outside the Workbench. If you change a resource outside the Workbench, you must refresh the Workbench before you continue to work with resources in the Workbench. This is also necessary if you modify resources using external editors. This will ensure that the resources in the Workbench are up-to-date.
This is especially important when using the Team support.
Workbench
Resources
Team programming with CVS