How To Fix PK321 - Several IDocs transferred to processing program simultaneously

SAP Error Message - Details

• Message type: E = Error

• Message class: PK - Production - KANBAN

• Message number: 321

• Message text: Several IDocs transferred to processing program simultaneously

What causes this issue?

Several IDocs were transferred simultaneously to the processing
program. However, only one IDoc can be posted.

System Response

IDoc inbound processing has been terminated.

How to fix this error?

Make sure that IDocs are transferred indiviually.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message PK321 - Several IDocs transferred to processing program simultaneously ?

  The SAP error message PK321 indicates that multiple IDocs (Intermediate Documents) have been transferred to a processing program simultaneously. This can occur in scenarios where the system is set up to process IDocs in parallel, but the processing program is not designed to handle concurrent processing of multiple IDocs.
  Cause:
  
  Concurrent Processing: The primary cause of this error is that the IDoc processing program is being invoked for multiple IDocs at the same time, which it cannot handle.
  Configuration Issues: The configuration of the IDoc processing might not be set up to allow for parallel processing, or the program itself may not be designed to handle multiple instances.
  Locking Mechanisms: The program may have locking mechanisms that prevent it from processing multiple IDocs simultaneously, leading to this error when multiple IDocs are sent for processing.
  
  Solution:
  
  Single Processing: Modify the configuration or the way the IDocs are processed to ensure that only one IDoc is processed at a time. This can be done by adjusting the settings in the IDoc processing program or the transaction that triggers the processing.
  Review Program Logic: If you have access to the ABAP code of the processing program, review it to ensure it can handle multiple IDocs. You may need to implement logic to queue the IDocs or process them sequentially.
  Batch Processing: If the processing program supports batch processing, consider grouping IDocs into batches that can be processed together, rather than sending them all at once.
  Increase Resources: If the processing program is resource-intensive, consider increasing the resources available to it (e.g., memory, processing power) to handle more concurrent processes.
  Error Handling: Implement error handling in the processing program to manage situations where multiple IDocs are received simultaneously, allowing it to queue or process them in a controlled manner.
  
  Related Information:
  
  Transaction Codes: You can use transaction codes like WE02 or WE05 to monitor IDocs and check their status.
  IDoc Processing Programs: Familiarize yourself with the specific IDoc processing programs being used in your environment, as different programs may have different capabilities regarding concurrent processing.
  SAP Notes: Check SAP Notes for any known issues or patches related to the specific IDoc processing program you are using. SAP frequently updates its documentation and provides solutions for common issues.
  Performance Tuning: If you frequently encounter this issue, consider performance tuning of the IDoc processing logic to improve its efficiency and ability to handle multiple IDocs.
  
  By addressing the underlying causes and implementing the suggested solutions, you should be able to resolve the PK321 error and improve the handling of IDocs in your SAP system.