Message type: E = Error
Message class:  SLEI_DEF_MSG - Message class for LEI design time linkages 
Message number: 120
Message text: Selected &1 generated design linkages are not allowed to delete
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The SAP error message SLEI_DEF_MSG120 indicates that there are selected design linkages in the system that cannot be deleted. This typically occurs in the context of SAP's Logistics Execution (LE) or similar modules where design linkages are used to manage relationships between different objects, such as materials, documents, or processes.
Cause: The error can be caused by several factors, including: Dependencies: The design linkages you are trying to delete may have dependencies or relationships with other objects that prevent their deletion. Status of Objects: The objects linked by the design linkages may be in a status that does not allow for deletion (e.g., they are locked, in use, or have been processed). Configuration Settings: Certain configuration settings in the system may restrict the deletion of specific linkages based on business rules or processes. Authorization Issues: The user may not have the necessary authorizations to delete the selected linkages.
Solution: To resolve this error, you can take the following
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