Message type: E = Error
Message class:  CNV_INDX - Messages for conversion of INDX-like tables 
Message number: 505
Message text: Variant of the RELID structure unknown (see details)
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The SAP error message CNV_INDX505, which states "Variant of the RELID structure unknown (see details)," typically occurs during data migration or conversion processes, particularly when using SAP's Data Migration tools or during the execution of certain programs that involve the RELID structure.
Cause: Unknown RELID Variant: The error indicates that the system encountered a variant of the RELID structure that it does not recognize. This could be due to: A missing or incorrectly defined variant in the system. An inconsistency in the data model or configuration. A version mismatch between the data being processed and the expected structure in the SAP system.
Configuration Issues: If the RELID structure has been customized or extended, and the new variants are not properly registered or defined in the system, this error can occur. Data Migration Issues: During data migration, if the source data contains variants that are not present in the target system, this error may arise.
Solution: Check Configuration: Verify the
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