How To Fix MD_SUBSTN021 - Rule &1 is relevant for applications used also by rule &2

SAP Error Message - Details

• Message type: E = Error

• Message class: MD_SUBSTN - Messages for Master Data Substitution

• Message number: 021

• Message text: Rule &1 is relevant for applications used also by rule &2

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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Smart SAP Assistant

• What is the cause and solution for SAP error message MD_SUBSTN021 - Rule &1 is relevant for applications used also by rule &2 ?

  The SAP error message MD_SUBSTN021 typically occurs in the context of the SAP Advanced Planning and Optimization (APO) module, particularly when dealing with substitution rules in the context of demand planning or supply network planning. This error indicates that there is a conflict or inconsistency in the substitution rules defined for certain applications.
  Cause:
  The error message "MD_SUBSTN021 Rule &1 is relevant for applications used also by rule &2" suggests that:
  
  There are two substitution rules defined in the system.
  Both rules are relevant for the same applications or planning areas, which can lead to conflicts in how the system processes data.
  This situation can arise when rules are not properly configured or when there are overlapping conditions that make it unclear which rule should take precedence.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Review Substitution Rules:
  
  Go to the transaction code where you manage substitution rules (e.g., /SAPAPO/SDP1 for demand planning).
  Identify the two rules mentioned in the error message (Rule &1 and Rule &2).
  Check the applications or planning areas that each rule is assigned to.
  
  
  
  Modify Rules:
  
  If both rules are indeed relevant for the same applications, consider modifying one of the rules to ensure that they do not overlap.
  You may need to change the conditions or the applications to which each rule applies.
  
  
  
  Deactivate Unused Rules:
  
  If one of the rules is not necessary, consider deactivating it to eliminate the conflict.
  
  
  
  Test Changes:
  
  After making changes, test the substitution rules to ensure that they work as expected without causing further errors.
  
  
  
  Consult Documentation:
  
  Refer to SAP documentation or help resources for detailed guidance on managing substitution rules in your specific version of SAP.
  
  
  
  Seek Help from SAP Support:
  
  If the issue persists or if you are unsure about making changes, consider reaching out to SAP support or consulting with an SAP expert.
  
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes for managing substitution rules, such as /SAPAPO/SDP1 for demand planning or /SAPAPO/SDP2 for supply planning.
  SAP Notes: Check for any SAP Notes related to substitution rules and error MD_SUBSTN021, as they may provide additional insights or patches.
  Documentation: Review the SAP Help Portal for detailed documentation on substitution rules and their configuration.
  
  By following these steps, you should be able to resolve the MD_SUBSTN021 error and ensure that your substitution rules are correctly configured.