How To Fix ED129 - Modules starting with 'SYST-' are C modules predefined by SAP

SAP Error Message - Details

• Message type: E = Error

• Message class: ED - ABAP/4 Editor messages

• Message number: 129

• Message text: Modules starting with 'SYST-' are C modules predefined by SAP

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 ED129 - Modules starting with 'SYST-' are C modules predefined by SAP ?

  The SAP error message ED129 indicates that you are trying to create or modify a module that starts with 'SYST-', which is reserved for predefined C modules in SAP. These modules are part of the SAP system and are not intended to be altered or created by users.
  
  Cause:
  The error occurs when:
  
  A user attempts to create a new module or function with a name that begins with 'SYST-'.
  There is an attempt to modify an existing module that is part of the SAP standard and starts with 'SYST-'.
  
  
  Solution:
  To resolve this error, you should:
  
  
  Rename the Module: If you are trying to create a new module, choose a different name that does not start with 'SYST-'. Use a naming convention that is unique and does not conflict with SAP's reserved names.
  
  
  Check Existing Modules: If you are trying to modify an existing module, ensure that you are not attempting to change a standard SAP module.