The Object API does not define a user interface other than a login dialog box. An application with its own user interface can use the Object API to access the GroupWise information store.
Third-party applications that run under the GroupWise Client can use a Custom 3rd-Party Object (C3PO). The C3PO interface simplifies extending GroupWise functionality. The C3PO specification replaces custom messages and custom commands in the GroupWise Client. Using the Object API, C3POs access and manipulate the GroupWise information store. C3POs must be registered in the Windows 95 system registry but the Object API does not use the system registry.