Message type: E = Error
Message class:  KK -  
Message number: 371
Message text: Derivation rules for model exist: model cannot be overwritten
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The SAP error message KK371 indicates that there are existing derivation rules for a particular model in the Controlling (CO) module, which prevents the model from being overwritten. This typically occurs when you attempt to change or delete a model that is currently in use or has dependencies defined in the system.
Cause: Existing Derivation Rules: The model you are trying to overwrite has derivation rules associated with it. These rules dictate how costs or revenues are allocated and are essential for the model's functionality. Model in Use: The model may be actively used in various transactions or reports, making it necessary to maintain its integrity. Configuration Settings: Certain configuration settings in the SAP system may restrict changes to models that have been defined with derivation rules.
Solution: To resolve the error, you can take the following steps: Review Derivation Rules: Navigate to the derivation rules associated with the model. You can do this through the SAP GUI
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