How To Fix MM042 - The internal number already exists

SAP Error Message - Details

• Message type: E = Error

• Message class: MM - Messages for material master maintenance and Customizing

• Message number: 042

• Message text: The internal number already exists

What causes this issue?

All proposed internal numbers already exist in the database. This is
probably due to an error in user exit MGA00002. However, in rare cases,
this message may also be displayed if the user exit is not activated.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

If the user exit is activated, check its source code.
If the user exit is not activated, try creating the material again.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message MM042 - The internal number already exists ?

  The SAP error message MM042 ("The internal number already exists") typically occurs in the Materials Management (MM) module when there is an attempt to create or modify a material master record, and the system detects that the internal number being used already exists in the database. This can happen during various transactions, such as creating a new material or changing an existing one.
  Causes:
  
  Duplicate Material Number: The most common cause is that the material number you are trying to create already exists in the system.
  Number Range Issues: If the number range for material numbers is not configured correctly, it may lead to conflicts where the system tries to assign a number that is already in use.
  Data Entry Errors: Manual entry errors can lead to attempts to create materials with existing numbers.
  System Configuration: Incorrect configuration in the material master settings or number range settings can also lead to this error.
  
  Solutions:
  
  
  Check Existing Material Numbers: Before creating a new material, check if the material number you are trying to use already exists. You can do this by using transaction codes like MM03 (Display Material) or MM02 (Change Material).
  
  
  Use a Different Number: If the material number already exists, choose a different number that is not in use.
  
  
  Review Number Range Configuration:
  
  Go to transaction code OMH1 to check the number range intervals for material numbers.
  Ensure that the number range is correctly defined and that there are no overlaps or gaps that could cause conflicts.
  
  
  
  Adjust Number Range: If necessary, you may need to adjust the number range settings to allow for new material numbers. This can be done by an SAP administrator.
  
  
  Consult with SAP Basis or Functional Team: If you are unable to resolve the issue, it may be necessary to consult with your SAP Basis or MM functional team for further investigation and assistance.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as MM01 (Create Material), MM02 (Change Material), MM03 (Display Material), and OMH1 (Maintain Number Ranges).
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message.
  Documentation: Review SAP documentation for best practices on material master data management and number range configuration.
  
  By following these steps, you should be able to identify the cause of the MM042 error and implement a solution to resolve it.