How To Fix /SAPAPO/RRP_CDOC021 - Select operation for backward/forward extension

/SAPAPO/RRP_CDOC021 - Overview

• Message type: E = Error

• Message class: /SAPAPO/RRP_CDOC -

• Message number: 021

• Message text: Select operation for backward/forward extension

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.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SAPAPO/RRP_CDOC021 - Select operation for backward/forward extension ?

  The SAP error message /SAPAPO/RRP_CDOC021 typically occurs in the context of Advanced Planning and Optimization (APO) when there is an issue with selecting operations for backward or forward extension in the production planning process. This error can arise due to various reasons, including configuration issues, data inconsistencies, or incorrect settings in the planning environment.
  
  Cause:
  
  Operation Selection Issues: The system is unable to select operations for backward or forward extension due to constraints in the production process or scheduling.
  Data Inconsistencies: There may be inconsistencies in the master data, such as the production version, routing, or work center data.
  Configuration Settings: Incorrect settings in the planning parameters or configuration of the planning book can lead to this error.
  Capacity Constraints: If there are capacity constraints in the work centers, the system may not be able to extend operations as required.
  
  
  Solution:
  
  Check Master Data: Verify the master data related to the production version, routing, and work centers.