Message type: E = Error
Message class:  UPO_MIG - Message Class for PRA->UOM Migration 
Message number: 219
Message text: Unit of Measurement group not found
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The SAP error message UPO_MIG219: Unit of Measurement group not found typically occurs during processes related to unit of measurement (UoM) conversions or when migrating data that involves UoM groups. This error indicates that the system is unable to find a specified unit of measurement group in the database. Causes: Missing UoM Group: The specified unit of measurement group does not exist in the system. This could be due to incorrect data entry or missing configuration. Data Migration Issues: If you are migrating data from another system or an older version of SAP, the UoM groups may not have been properly transferred or created in the new system. Configuration Errors: The UoM group may not have been set up correctly in the configuration settings of SAP. Incorrect Master Data: The master data being used may reference a UoM group that has not been defined in the system. Solutions: Check UoM Group Configuration: Go to the transaction code OMN3
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