How To Fix MW638 - Material or material group missing for model allocation rule

SAP Error Message - Details

• Message type: E = Error

• Message class: MW - Messages IS-R / Allocation Tables

• Message number: 638

• Message text: Material or material group missing for model allocation rule

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.

Unfortunately, there isn't any extra information in this error notice.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

Smart SAP Assistant

• What is the cause and solution for SAP error message MW638 - Material or material group missing for model allocation rule ?

  The SAP error message MW638 ("Material or material group missing for model allocation rule") typically occurs in the context of model allocation in SAP, particularly when dealing with variant configuration or when trying to allocate materials to a model. This error indicates that the system cannot find a specified material or material group that is required for the model allocation rule.
  Causes:
  
  Missing Material: The material you are trying to allocate does not exist in the system or is not correctly defined.
  Missing Material Group: The material group associated with the model allocation rule is not defined or is missing.
  Incorrect Configuration: The model allocation rule may not be correctly configured, leading to the system being unable to find the necessary materials or groups.
  Authorization Issues: The user may not have the necessary authorizations to view or access the materials or material groups.
  Data Inconsistencies: There may be inconsistencies in the master data, such as missing entries in the material master or incorrect settings in the allocation rules.
  
  Solutions:
  
  Check Material Existence: Verify that the material you are trying to allocate exists in the system. You can do this by using transaction codes like MM03 (Display Material) to check the material master data.
  Verify Material Group: Ensure that the material group associated with the model allocation rule is defined and correctly set up in the system.
  Review Model Allocation Rules: Go to the model allocation rules configuration and ensure that all necessary materials and groups are correctly assigned. You can check this in the configuration settings for the model.
  Check Authorizations: Ensure that the user has the necessary authorizations to access the materials and material groups involved in the allocation.
  Data Consistency Check: Run consistency checks on the material master data to identify any discrepancies or missing entries. You can use transaction codes like MM02 (Change Material) to update any missing information.
  Consult Documentation: Review SAP documentation or help resources for specific guidance on model allocation rules and related configurations.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as MM01 (Create Material), MM02 (Change Material), and MM03 (Display Material) for managing material data.
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message. SAP Notes can provide specific fixes or workarounds.
  Training and Documentation: Consider reviewing SAP training materials or documentation related to variant configuration and model allocation to better understand the setup and requirements.
  
  If the issue persists after checking the above points, it may be beneficial to consult with your SAP support team or a functional consultant who specializes in materials management or variant configuration.