Message type: E = Error
Message class:  CNV_PE_S4 - Messages for Posting Engine S/4 Content 
Message number: 018
Message text: &1 worklist items for inactive Cost Center(s) are not added to worklist
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The SAP error message CNV_PE_S4018 indicates that there are worklist items related to inactive Cost Centers that are not being added to the worklist during a data migration or conversion process. This error typically arises in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other conversion tools.
Cause: Inactive Cost Centers: The primary cause of this error is that the Cost Centers referenced in the worklist are inactive. Inactive Cost Centers cannot be processed or included in the worklist for migration or conversion.
Configuration Issues: There may be configuration settings that prevent inactive Cost Centers from being included in the worklist. Data Integrity: The data being migrated may have integrity issues, such as references to Cost Centers that are not active in the system.
Solution: Activate Cost Centers: If the Cost Centers are supposed to be active, you can activate them in the SAP system. This can be done
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