Message type: E = Error
Message class:  /CCIS/TAX -  
Message number: 142
Message text: Exit pool must be in the customer namespace
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The SAP error message /CCIS/TAX142 Exit pool must be in the customer namespace typically occurs in the context of SAP's Customer Connection and Enhancement Framework, particularly when dealing with user exits or enhancements that are not properly defined in the customer namespace.
Cause: Namespace Issue: The error indicates that the exit pool (a collection of user exits) you are trying to use or create is not located in the customer namespace. In SAP, customer-specific developments should be done in the customer namespace (usually starting with "Z" or "Y") to avoid conflicts with standard SAP objects. Incorrect Configuration: The exit pool may have been defined in a standard SAP namespace instead of the customer namespace, which is not allowed for customer-specific enhancements.
Solution: Check Namespace: Verify the namespace of the exit pool you are trying to use. It should be in the customer namespace (e.g., Z or Y). If it is not, you will need to
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