How To Fix CL556 - Class type & is only used internally

SAP Error Message - Details

• Message type: E = Error

• Message class: CL - Classification

• Message number: 556

• Message text: Class type & is only used internally

What causes this issue?

You have entered a class type that is only used internally.
You cannot create a class with this class type.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Use the <PF>Change class type</> pushbutton to display a list of all
the class types you can use per object type, and select the class type
you require. Internal class types are not included in this list.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CL556 - Class type & is only used internally ?

  The SAP error message CL556 indicates that the class type you are trying to use is designated for internal use only. This typically occurs when you attempt to create or manipulate a class of a type that is not intended for external use or is restricted to specific internal processes within SAP.
  Cause:
  
  Class Type Restriction: The class type you are trying to work with is defined in the SAP system as an internal class type. This means it is not meant to be instantiated or used in the same way as other class types (like public or abstract classes).
  Incorrect Class Type: You may be using the wrong class type for your intended purpose. For example, trying to create an instance of a class that is meant for internal SAP processes rather than for user-defined or application-specific purposes.
  
  Solution:
  
  Check Class Type: Verify the class type you are trying to use. You can do this by checking the class definition in the Class Builder (transaction SE24). Ensure that you are using a class type that is appropriate for your needs.
  Use Appropriate Class: If you need to create a class, ensure that you are using a class type that is intended for external use (like type 1 for public classes).
  Consult Documentation: Review SAP documentation or help resources to understand the purpose of the class type you are dealing with and find alternatives if necessary.
  Contact SAP Support: If you believe you are encountering this error inappropriately, consider reaching out to SAP support for further assistance.
  
  Related Information:
  
  
  Class Types in SAP: SAP has several class types, including:
  
  Type 1: Public classes that can be instantiated and used freely.
  Type 2: Abstract classes that cannot be instantiated directly.
  Type 3: Interfaces that define methods but do not provide implementations.
  Type 4: Internal classes that are used by SAP for specific purposes and are not intended for external use.
  
  
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as SE24 (Class Builder) and SE80 (Object Navigator) to explore class definitions and their types.
  
  
  By following these steps, you should be able to resolve the error and understand the limitations of the class type you are working with.