Message type: E = Error
Message class:  CNV_DMC_SIN - Messages for s-innovations migration 
Message number: 309
Message text: Unexpected transaction number of facility &1 in the translation rule &2
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The SAP error message CNV_DMC_SIN309 indicates that there is an unexpected transaction number associated with a facility in the translation rule during a data migration or conversion process. This error typically arises in the context of using the SAP Data Migration Cockpit (DMC) or during the execution of a data migration project.
Cause: The error can be caused by several factors, including: Incorrect Configuration: The translation rule may not be properly configured, leading to mismatches in transaction numbers. Data Inconsistencies: There may be inconsistencies in the data being migrated, such as missing or incorrect facility identifiers. Version Mismatch: The version of the migration tool or the source system may not be compatible with the target system. Custom Logic: If there are custom enhancements or logic applied to the migration process, they may not be handling the transaction numbers correctly.
Solution: To resolve the CNV_DMC_SIN309 error, you can follow these steps: Check Translation Rules: Review the translation rules defined in
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