Message type: E = Error
Message class:  CNVMBT - Messages for MBT/API/PCL 
Message number: 204
Message text: Jobs Control checks running...
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The SAP error message CNVMBT204 typically relates to issues encountered during the execution of a job in the SAP system, particularly in the context of data migration or conversion processes. This error message indicates that there are control checks that are still running, which may prevent the job from proceeding or completing successfully.
Cause: Concurrent Jobs: The error may occur if there are multiple jobs running simultaneously that are trying to access the same resources or data. Locking Issues: The system may be experiencing locking issues where one job is holding a lock on a resource that another job needs to access. Long-Running Processes: If a previous job is taking longer than expected to complete, it may cause subsequent jobs to be queued or delayed.
Configuration Issues: There may be configuration settings in the job control that are not set correctly, leading to conflicts.
Solution: Check Job Status: Use transaction codes like SM37 to check the status
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CNVMBT203 Jobs Control checks completed.
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CNVMBT205 Semaphores Control checks completed.
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CNVMBT206 Semaphores Control checks running...
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