How To Fix CN818 - Relationships cannot be maintained

CN818 - Overview

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 818

• Message text: Relationships cannot be maintained

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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CN818 - Details

• The SAP error message CN818 ("Relationships cannot be maintained") typically occurs in the context of project management or network planning within the SAP system, particularly when dealing with the assignment of relationships between activities in a project or network.
  
  Cause:
  The error CN818 can arise due to several reasons, including:
  
  Invalid Activity Status: The activity you are trying to maintain relationships for may be in a status that does not allow changes (e.g., completed or closed).
  Incorrect Project Structure: The project structure may not allow for the relationships you are trying to create or modify. For example, if the activities are not properly linked or if there are inconsistencies in the project hierarchy.
  Missing Authorizations: The user may not have the necessary authorizations to maintain relationships for the activities in question.
  Locked Activities: The activities may be locked for editing due to ongoing processes or other users working on them.
  System 
  Configuration Issues: There may be configuration