Class Designer is unable to display this type
Class Designer is unable to display this type.
This may be due to several limitations of the tool, click help for more information.
This is a general error that is thrown when Class Designer cannot display a type because it has lost track of the source code or because the source code is unrecognizable or is not a valid C++ type.
To correct this error
Ensure that the type you entered is a valid type for the language and that Class Designer supports it. For more information about the functionality and limitations of Class Designer, see Viewing Types and Relationships on Class Diagrams or Working with Visual C++ Code in Class Designer.
If you modify your project structure or move source files within your project, Class Designer can lose track of the type. (This is especially true of the source type of a typedef, base classes, or association types.) If this is the case, you should drag the modified or relocated source code to the class diagram again to redisplay it.