How To Fix ON121 - Selection of all classes switched on or off

SAP Error Message - Details

• Message type: E = Error

• Message class: ON - Tools in area Object Modeler / Object Editor

• Message number: 121

• Message text: Selection of all classes switched on or off

What causes this issue?

You have chosen Edit->Select on/off->Classes. On this and the following
screens all classes will now be displayed selected or unselected.

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?

No action is required. This is just for your information.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message ON121 - Selection of all classes switched on or off ?

  The SAP error message ON121, which states "Selection of all classes switched on or off," typically occurs in the context of class selection in the SAP system, particularly when dealing with classification or variant configuration.
  Cause:
  This error message usually arises when there is a conflict in the selection criteria for classes in a classification system. It can occur if:
  
  The user has attempted to select or deselect all classes in a way that is not allowed by the system.
  There may be inconsistencies in the configuration settings or the way classes are defined in the system.
  The selection criteria may not be properly set, leading to ambiguity in the selection process.
  
  Solution:
  To resolve the ON121 error, you can try the following steps:
  
  
  Check Selection Criteria: Review the selection criteria you are using. Ensure that you are not trying to select or deselect all classes simultaneously in a way that conflicts with the system's rules.
  
  
  Review Class Definitions: Go to the classification settings and check the definitions of the classes involved. Ensure that they are correctly configured and that there are no missing or incorrect entries.
  
  
  Use Specific Class Selection: Instead of selecting all classes, try to specify the individual classes you want to work with. This can help avoid the conflict that leads to the error.
  
  
  Consult Documentation: Refer to SAP documentation or help resources related to classification and variant configuration for more detailed guidance on how to properly set up class selections.
  
  
  Check User Authorizations: Ensure that you have the necessary authorizations to perform the actions you are attempting. Sometimes, lack of permissions can lead to unexpected errors.
  
  
  Contact SAP Support: If the issue persists after trying the above steps, consider reaching out to SAP support for further assistance. They may provide insights specific to your system configuration.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CL02 (Change Class), CL03 (Display Class), and CL01 (Create Class) to manage class definitions.
  SAP Notes: Check for any SAP Notes related to this error message, as they may provide patches or additional solutions.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed, and solutions shared.
  
  By following these steps, you should be able to address the ON121 error and continue with your classification tasks in SAP.