How To Fix CJ171 - Your relationship's predecessor or successor is not an activity

CJ171 - Overview

• Message type: E = Error

• Message class: CJ - Project master data and structure

• Message number: 171

• Message text: Your relationship's predecessor or successor is not an activity

What causes this issue?

You want to create a relationship between two project objects.
However, at least one of these objects is not an activity.

System Response

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

How to fix this error?

Create relationships between activities only.

Error message extract from SAP system. Copyright SAP SE.

CJ171 - Details

• The SAP error message CJ171 indicates that there is an issue with the relationship defined in a project structure, specifically that either the predecessor or successor in a relationship is not recognized as an activity. This error typically occurs in the Project System (PS) module when you are trying to create or modify relationships between activities in a project.
  
  Cause:
  
  Incorrect Object Type: The predecessor or successor you are trying to link is not an activity. It could be a milestone, a WBS element, or another type of object that does not support relationships in the same way that activities do.
  Inactive or Deleted Activities: The activity you are trying to reference may have been deleted or is currently inactive.
  Incorrect Configuration: There may be configuration issues in the project structure that prevent the system from recognizing the relationship correctly.
  
  
  Solution:
  
  Verify Object Types: Check the objects you are trying to link. Ensure that both the