Message type: E = Error
Message class:  MMRP01 - Rapid Planning Matrix 
Message number: 028
Message text: RPM has not been activated for product &1 in location &2
Product &V1& in location &V2& is not flagged for planning with the RPM.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Enter indicator <LS>4 for exploding iPPE with the RPM</> in the
Explosion field on tab page PP/DS in the product master.
You can use the <DS:TRAN.MDRPM>Additional Data for RPM Products</>
transaction to enter additional parameters.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message MMRP01028 indicates that the "Replenishment Planning" (RPM) has not been activated for a specific product in a given location. This error typically arises in the context of materials management and inventory control within SAP, particularly when trying to perform operations related to replenishment planning.
Cause: The error occurs when: The Replenishment Planning (RPM) functionality has not been activated for the specified product (material) in the specified location (plant/storage location). The product may not be set up correctly in the system for replenishment planning. The necessary configuration settings for RPM may not have been completed in the system.
Solution: To resolve the MMRP01028 error, you can follow these steps: Check RPM Activation: Go to the material master record for the product in question. Navigate to the "MRP" (Material Requirements Planning) view. Ensure that the "Replenishment Planning" checkbox is activated for the relevant plant/storage location. Activate RPM: If RPM is not activated, you can activate it by: Going to the transaction code
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