How To Fix EI321 - Input of document number is only possible with external number assignment

EI321 - Overview

• Message type: E = Error

• Message class: EI - Foreign Trade: Gen. Output

• Message number: 321

• Message text: Input of document number is only possible with external number assignment

What causes this issue?

The indicator for document number required entry was set, but either an
internal number assignment or no number assignment is preset for this
output type.
The SAP system automatically assigns consecutive numbers during internal
number assignment. It is not possible to make an entry externally. This
indicator is only suitable for external number assignment.

System Response

The system responds with an error message.

How to fix this error?

Deactivate the indicator for the required entry of the document number
or choose an external number assignment.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message EI321 - Input of document number is only possible with external number assignment ?

  The SAP error message EI321, which states "Input of document number is only possible with external number assignment," typically occurs when you are trying to enter a document number manually in a transaction that is configured to use external number assignment, but the system is set to use internal number assignment instead.
  
  Cause:
  
  Number Assignment Configuration: The document type you are trying to use is configured for external number assignment in the system settings, but the system is currently set to use internal number assignment.
  Document Type Settings: The specific document type you are working with may have been set up incorrectly, or the configuration may not match the intended use.
  User Authorization: In some cases, user roles and authorizations may restrict the ability to enter document numbers manually.
  
  
  Solution:
  
  
  Check Document Type Configuration:
  
  Go to the transaction code OBY6 (for Financial Accounting) or OBA7 (for other document types) to check the configuration of the document type