Message type: E = Error
Message class:  CNV_PE - General messages for posting engine 
Message number: 059
Message text: &1 execution rule not maintained yet
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The SAP error message CNV_PE059 typically indicates that there is an execution rule that has not been maintained for a specific process or operation in the context of a data migration or conversion project. This error is often encountered in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other conversion tools.
Cause: Missing Execution Rule: The primary cause of this error is that the execution rule for the specified process has not been defined or maintained in the system. This could happen if the configuration for the data migration process is incomplete. Incorrect Configuration: There may be a misconfiguration in the migration project settings or the specific data migration object. Version Mismatch: If you are using a version of the migration tool that does not support certain execution rules, this error may occur.
Solution: Maintain Execution Rules: Go to the relevant transaction or configuration area where execution rules are defined
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