Message type: E = Error
Message class:  RSO_SEGR - Messages for TLOGO = SEGR  (Semantic Group of ADSOs) 
Message number: 261
Message text: aDSO '&1' will not be part of the group metadata anymore
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The SAP error message RSO_SEGR261 indicates that a DataStore Object (DSO) is no longer part of the group metadata in the context of SAP BW (Business Warehouse) or SAP BW/4HANA. This typically occurs when there are changes in the configuration or structure of the DSO or when the DSO is no longer relevant for the specific data flow or process.
Cause: DSO Deactivation: The DSO may have been deactivated or removed from the data flow. Changes in Data Model: Changes in the data model or the way data is being processed can lead to the DSO being excluded from the group metadata. Transport Issues: If the DSO was transported from one system to another, there might be inconsistencies in the metadata. Configuration Changes: Changes in the configuration of the InfoProvider or the data flow can lead to this error. Versioning Issues: If there are multiple versions of the DSO, the system might be referencing an outdated
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