Message type: E = Error
Message class:  /SCMB/TG_NACH -  
Message number: 051
Message text: Selection type &1 does not exist
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The SAP error message /SCMB/TG_NACH051 Selection type &1 does not exist typically occurs in the context of SAP Supply Chain Management (SCM) when a specific selection type is referenced in a transaction or process, but it is not defined in the system.
Cause: Missing Configuration: The selection type referenced in the error message is not configured in the system. This could happen if the selection type was deleted or never created. Typographical Error: There may be a typo in the selection type being referenced, leading to the system not recognizing it. Transport Issues: If the selection type was recently transported from another system, it may not have been included in the transport request or may not have been activated properly.
Solution: Check Configuration: Go to the relevant configuration settings in SAP SCM where selection types are defined. This is usually found in the customizing settings under the relevant module (e.g., /SCMB/). Verify if the selection type exists. If
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