How To Fix DPR_BAPI155 - Predecessor and/or successor do not allow any changes to the relationship

SAP Error Message - Details

• Message type: E = Error

• Message class: DPR_BAPI - Messages for BAPIs in Project Management

• Message number: 155

• Message text: Predecessor and/or successor do not allow any changes to the relationship

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.

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Smart SAP Assistant

• What is the cause and solution for SAP error message DPR_BAPI155 - Predecessor and/or successor do not allow any changes to the relationship ?

  The SAP error message DPR_BAPI155 indicates that there is an issue with the relationship between predecessor and successor tasks in a project. This error typically arises when you attempt to modify a relationship that is not allowed due to the current status or configuration of the tasks involved.
  Causes:
  
  Status of Tasks: The predecessor or successor tasks may be in a status that does not allow changes. For example, if a task is completed or locked, you may not be able to modify its relationships.
  Project Settings: Certain project settings or configurations may restrict changes to task relationships. This can include settings related to project planning or specific project types.
  Dependencies: The relationship you are trying to change may violate existing dependencies or constraints set on the tasks.
  User Authorizations: The user may not have the necessary authorizations to make changes to the project or its tasks.
  
  Solutions:
  
  Check Task Status: Verify the status of both the predecessor and successor tasks. If they are completed or locked, you may need to unlock them or change their status before making modifications.
  Review Project Settings: Look into the project settings to see if there are any restrictions on changing task relationships. Adjust the settings if necessary.
  Modify Dependencies: Ensure that the changes you are trying to make do not violate any existing dependencies. You may need to adjust other relationships or constraints first.
  User Authorizations: Confirm that you have the appropriate authorizations to make changes to the project. If not, contact your system administrator to obtain the necessary permissions.
  Use Transaction Codes: If you are using a specific transaction code to make changes, ensure that you are following the correct procedure. Sometimes, using a different transaction or method can help resolve the issue.
  
  Related Information:
  
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message. SAP frequently updates its knowledge base with solutions for common problems.
  Documentation: Review the SAP documentation for project management and task relationships to better understand the rules and constraints that apply.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed. Other users may have encountered the same error and found solutions.
  
  If the issue persists after trying the above solutions, consider reaching out to your SAP support team for further assistance.