Message type: E = Error
Message class:  CNV_CMIS_A_20 - Message class for Cross-Client Customizing Comparison (SLO) 
Message number: 288
Message text: Sorry! Selected list contains already excluded table entries.
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The SAP error message CNV_CMIS_A_20288 typically occurs during data migration or conversion processes, particularly when using the SAP Conversion Management Information System (CMIS). This error indicates that the selected list contains entries that have already been excluded from the migration process.
Cause: The error is caused by attempting to include or process table entries that have already been marked as excluded in the migration process. This can happen due to: Duplicate Selection: The user may have inadvertently selected entries that were previously excluded. Incorrect Configuration: The migration settings may not be correctly configured, leading to confusion about which entries are included or excluded. Data Integrity Issues: There may be issues with the data itself, such as inconsistencies or conflicts that lead to certain entries being excluded.
Solution: To resolve this error, you can take the following steps: Review the Excluded Entries: Check the list of excluded entries to understand why they were excluded. This can often be done
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