How To Fix 8A556 - Format of reference document number is invalid

SAP Error Message - Details

• Message type: E = Error

• Message class: 8A - Messages for Argentina

• Message number: 556

• Message text: Format of reference document number is invalid

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 8A556 - Format of reference document number is invalid ?

  The SAP error message 8A556 indicates that the format of the reference document number is invalid. This error typically occurs when the system expects a specific format for the reference document number, but the input does not conform to that format.
  Causes:
  
  Incorrect Format: The reference document number may not match the expected format defined in the system settings. This could include issues with length, character types (e.g., numeric vs. alphanumeric), or specific prefixes/suffixes.
  Configuration Issues: The configuration settings for document number ranges or formats may not be set up correctly in the SAP system.
  User Input Error: The user may have entered the reference document number incorrectly, including typos or incorrect characters.
  Data Migration Issues: If data has been migrated from another system, the reference document numbers may not conform to the expected format in SAP.
  
  Solutions:
  
  Check Input: Verify that the reference document number is entered correctly. Ensure that it adheres to the expected format (length, character type, etc.).
  Review Configuration: Check the configuration settings for document number formats in the relevant SAP module (e.g., FI, MM, SD). This can usually be done in the customizing settings (transaction SPRO).
  Consult Documentation: Refer to the SAP documentation or help files for the specific module you are working with to understand the expected format for reference document numbers.
  Contact Support: If the issue persists, consider reaching out to your SAP support team or consulting with an SAP expert to review the configuration and settings.
  Test with Sample Data: If possible, test the entry with known valid reference document numbers to see if the issue is with the specific number being used.
  
  Related Information:
  
  Transaction Codes: Depending on the module, you may need to check specific transaction codes related to document entry (e.g., FB60 for vendor invoices, FB70 for customer invoices).
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional guidance.
  User Exits or BAdIs: If custom logic is implemented in your SAP system, check for any user exits or BAdIs that might affect the validation of the reference document number.
  
  By following these steps, you should be able to identify the cause of the error and implement a solution to resolve it.