How To Fix /SAPAPO/DM_SCHEDFAIL028 - Locked activity chain of other activities is blocking gap for activity

/SAPAPO/DM_SCHEDFAIL028 - Overview

• Message type: E = Error

• Message class: /SAPAPO/DM_SCHEDFAIL -

• Message number: 028

• Message text: Locked activity chain of other activities is blocking gap for activity

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /SAPAPO/DM_SCHEDFAIL028 - Locked activity chain of other activities is blocking gap for activity ?

  The SAP error message /SAPAPO/DM_SCHEDFAIL028 indicates that a locked activity chain is preventing the scheduling of a specific activity in the SAP Advanced Planning and Optimization (APO) module. This typically occurs when there are dependencies between activities in a planning run, and one or more of those activities are locked or not yet completed.
  
  Cause:
  
  Locked Activities: The activity chain that the current activity depends on is locked. This can happen if another process is currently executing or if there are manual locks in place.
  Dependency Issues: The activity you are trying to schedule has dependencies on other activities that have not been completed or are in a locked state.
  Planning Version: The planning version being used may have inconsistencies or issues that prevent the scheduling of activities.
  Resource Constraints: There may be resource constraints that are causing the activities to be locked or delayed.
  
  
  Solution:
  
  Check Locks: Use transaction codes like SM12 to check for any