How To Fix /AIF/SERIALIZATION021 - The interface's serialization type is not "External Index"

/AIF/SERIALIZATION021 - Overview

• Message type: E = Error

• Message class: /AIF/SERIALIZATION -

• Message number: 021

• Message text: The interface's serialization type is not "External Index"

Self-Explanatory Message

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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 /AIF/SERIALIZATION021 - The interface's serialization type is not "External Index" ?

  The SAP error message /AIF/SERIALIZATION021 indicates that there is an issue with the serialization type of an interface in the Application Interface Framework (AIF). Specifically, it states that the interface's serialization type is not set to "External Index," which is required for the operation you are trying to perform.
  
  Cause:
  
  Incorrect Serialization Type: The interface you are working with is configured with a serialization type that does not match the expected "External Index." This could be due to a misconfiguration in the AIF settings.
  Interface Configuration: The interface might have been set up incorrectly, or the serialization type may have been changed after the initial configuration.
  Versioning Issues: If there have been updates or changes to the AIF or the interface, it may have affected the serialization settings.
  
  
  Solution:
  
  
  Check Interface Configuration:
  
  Go to the AIF configuration for the specific interface that is causing the error.
  Verify the serialization type setting. It should be set to "External Index."
  If