How To Fix B1521 - IDoc type & already exists in packet &

B1521 - Overview

• Message type: E = Error

• Message class: B1 - ALE group messages

• Message number: 521

• Message text: IDoc type & already exists in packet &

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 B1521 - IDoc type & already exists in packet & ?

  The SAP error message B1521 indicates that there is a duplicate IDoc type in the IDoc packet. This typically occurs when the same IDoc type is being processed multiple times within a single IDoc packet, which is not allowed.
  
  Cause:
  
  Duplicate IDoc Types: The primary cause of this error is that the same IDoc type is included more than once in the same IDoc packet.
  
  Configuration Issues: There may be issues in the configuration of the IDoc processing or the way the IDocs are being generated.
  Data Transmission Errors: Sometimes, errors in data transmission or processing can lead to duplicates being created.
  
  
  Solution:
  
  Check IDoc Packet: Review the IDoc packet to ensure that each IDoc type is unique. You can do this by checking the IDoc control record and the data segments.
  Modify IDoc Generation Logic: If you are generating IDocs programmatically, ensure that your logic does not create duplicates. This may involve checking for existing IDocs