Message type: E = Error
Message class:  COM_PRCAT - Product Category 
Message number: 081
Message text: Product references not active: Set type &1 cannot be assigned
The set type &V1& is required for product references only. However, as
the product reference function has not been activated in your system it
does not make sense to assign this set type to the category.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Product references can be activated in Customizing.
To do this from here, choose <LS>Customizing</> in the <LS>Performance
Assistant</> toolbar.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message COM_PRCAT081 indicates that there is an issue with product references in the context of a specific set type. The message states that the product references are not active, which means that the system cannot assign the specified set type to the product.
Cause: The error typically arises due to one of the following reasons: Inactive Product Reference: The product reference you are trying to use is not active in the system. This could be due to it being deactivated or not properly configured. Set Type Configuration: The set type you are trying to assign may not be correctly configured or may not be allowed for the product reference in question. Missing Master Data: There may be missing or incomplete master data related to the product or the set type. Authorization Issues: There could be authorization issues preventing the assignment of the set type to the product.
Solution: To resolve the error, you can take
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