Message type: E = Error
Message class:  RSO_SEGR - Messages for TLOGO = SEGR  (Semantic Group of ADSOs) 
Message number: 121
Message text: Error in deserialization for Semantic Group '&1'
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The SAP error message RSO_SEGR121, which indicates "Error in deserialization for Semantic Group '&1'", typically occurs in the context of SAP BW (Business Warehouse) or SAP BW/4HANA when there is an issue with the data model or the semantic group configuration. This error can arise during the execution of queries, data extraction, or when trying to access certain data models. Causes: Corrupted Data Model: The semantic group or the associated data model may be corrupted or improperly configured. Version Mismatch: There may be a version mismatch between the data model and the underlying data source or between different components of the SAP system. Transport Issues: If the semantic group was transported from one system to another, there may have been issues during the transport process that led to inconsistencies. Missing Objects: Required objects (like InfoObjects, InfoProviders, etc.) that the semantic group depends on may be missing or not activated. Authorization Issues: Lack of proper authorizations to
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