How To Fix CNVMBT028 - Expert mode not allowed, program must succeed once

CNVMBT028 - Overview

• Message type: E = Error

• Message class: CNVMBT - Messages for MBT/API/PCL

• Message number: 028

• Message text: Expert mode not allowed, program must succeed once

Self-Explanatory Message

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CNVMBT028 - Details

• The SAP error message CNVMBT028 indicates that the program is running in a mode that does not allow for expert mode operations, and it requires that the program must succeed at least once before proceeding. This error typically arises in the context of data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
  
  Cause:
  
  Expert Mode Not Enabled: The program is being executed in a standard mode where expert features are not permitted. This can happen if the user does not have the necessary authorizations or if the configuration does not allow for expert mode operations.
  Initial Execution Requirement: The program is designed to require a successful run in a non-expert mode before it can be executed in expert mode. This is often a safeguard to ensure that the initial data load is successful before allowing more complex operations.
  
  
  Solution:
  
  Run in Standard Mode: First, ensure that you run