How To Fix C1171 - Enter a class and a class type

SAP Error Message - Details

• Message type: E = Error

• Message class: C1 - Characteristics maintenance messages

• Message number: 171

• Message text: Enter a class and a class type

What causes this issue?

A characteristic of data type ADT (abstract data type) must contain
both a class and a class type. At least one of these entries is
missing.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message C1171 - Enter a class and a class type ?

  The SAP error message C1171 ("Enter a class and a class type") typically occurs in the context of classification in SAP, particularly when working with the classification system (e.g., when creating or modifying a material master, equipment, or other objects that utilize classification).
  Cause:
  This error message is triggered when the system expects you to enter a class and a class type, but either one or both of these fields are left blank. The classification system in SAP requires that each object is assigned to a specific class (which groups similar objects) and a class type (which defines the characteristics of the class).
  Solution:
  To resolve this error, you should:
  
  
  Check Input Fields: Ensure that you have entered both a class and a class type in the relevant fields. 
  
  Class: This is usually a specific identifier for the classification group.
  Class Type: This defines the type of classification (e.g., material, equipment, etc.).
  
  
  
  Use the Correct Class Type: Make sure that the class type you are trying to use is valid for the object you are working with. You can check the available class types in the classification system.
  
  
  Create or Assign Classes: If you do not have the necessary class or class type, you may need to create a new class or ensure that the class you are trying to use is properly defined in the system.
  
  
  Authorization: Ensure that you have the necessary authorizations to create or modify classes and class types in the SAP system.
  
  
  Consult Documentation: If you are unsure about the correct class or class type to use, refer to your organization's documentation or consult with a colleague who is familiar with the classification system in your SAP environment.
  
  
  Related Information:
  
  Transaction Codes: You may use transaction codes like CL02 (Change Class), CL03 (Display Class), or CL01 (Create Class) to manage classes in the classification system.
  SAP Help Documentation: Refer to the SAP Help Portal for detailed information on classification and how to manage classes and class types.
  Customizing Settings: If you are an administrator, check the customizing settings in SPRO under "Logistics General" -> "Material Master" -> "Basic Settings" -> "Define Classes" to ensure that the classes and class types are set up correctly.
  
  By following these steps, you should be able to resolve the C1171 error and successfully enter the required class and class type in your SAP system.