Message type: E = Error
Message class:  ADPIC -  
Message number: 021
Message text: &: & Material belongs to a restricted interchangeability relationship
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The SAP error message ADPIC021 indicates that a material is part of a restricted interchangeability relationship. This typically occurs in scenarios where materials are defined in such a way that they cannot be interchanged due to specific business rules or restrictions set in the system.
Cause: Interchangeability Settings: The materials involved may have been set up with specific interchangeability rules that restrict their use in certain contexts. This could be due to quality, compliance, or other business requirements. Material Master Data: The material master data may have been configured incorrectly, or the interchangeability relationships may not have been properly defined. Status of Materials: One or both materials may have a status that prevents them from being interchanged, such as being flagged as obsolete or restricted for use in certain transactions.
Solution: Review Interchangeability Settings: Check the interchangeability settings for the materials involved. You can do this by navigating to the material master data and reviewing the
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