Message type: E = Error
Message class:  CNVMBTPEM - PEM (Process Execution Manager) 
Message number: 028
Message text: Called dequeue for &1.
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The SAP error message CNVMBTPEM028 typically relates to issues encountered during the execution of a data migration or conversion process, particularly when using the SAP Landscape Transformation (SLT) or SAP Data Services. The message indicates that there was a problem with the dequeue operation for a specific object or resource.
Cause: The error message CNVMBTPEM028 Called dequeue for &1 can occur due to several reasons, including: Locking Issues: The object or resource that the process is trying to access is currently locked by another process. This can happen if multiple processes are trying to access the same data simultaneously. Transaction Rollback: If a previous transaction failed or was rolled back, it might leave the system in a state where the dequeue operation cannot be completed. System Performance: High system load or performance issues can lead to timeouts or failures in processing dequeue requests.
Configuration Issues: Incorrect configuration settings in the migration or transformation process can lead
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