Message type: E = Error
Message class:  CNV_21526 - Client Rename 
Message number: 011
Message text: A blank field may be filled with client &1
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The SAP error message CNV_21526011 indicates that a blank field in a certain context may be filled with the client number specified (denoted as &1). This error typically arises during data migration or conversion processes, particularly when using SAP's data migration tools or during system upgrades.
Cause: The error occurs when the system encounters a blank field that is expected to have a value, and it suggests that the client number (which is a unique identifier for a specific instance of an SAP system) could be used to fill that blank. This situation may arise due to: Data Inconsistencies: The source data may have missing values that are required for the target system.
Configuration Issues: The mapping or transformation rules defined in the migration process may not account for certain fields being blank. Business Logic: Certain fields may be mandatory in the target system, and if they are blank in the source data, the system
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