Message type: E = Error
Message class:  FKKBW_E - Message for BW Extraction 
Message number: 051
Message text: *************051-100 Reserved for RETBW Extraction**********************
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The SAP error message FKKBW_E051, which states "*****051-100 Reserved for RETBW Extraction**," typically occurs in the context of SAP BW (Business Warehouse) when there is an issue related to the extraction of data from the SAP system to the BW system. This error is specifically related to the extraction of data from the Financial Accounting (FI) module.
Cause: Reserved Number Range: The error indicates that the number range from 051 to 100 is reserved for RETBW extraction. This means that the system is trying to use a number range that is not available for the current extraction process.
Configuration Issues: There may be configuration issues in the data source or the extraction process that are causing the system to attempt to use a reserved number range. Data Source Settings: The data source settings in the BW system may not be correctly configured to handle the extraction from the source system.
Solution: Check Number Range Configuration: Verify
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