Message type: E = Error
Message class:  CNV_PE - General messages for posting engine 
Message number: 490
Message text: Not allowed to change execution rule step
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The SAP error message CNV_PE490 typically occurs during the execution of a data migration or conversion process, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there is an attempt to change the execution rule of a step that is not allowed to be modified at that point in the process.
Cause: Execution Rule Restrictions: The execution rules for certain steps in the migration process are predefined and cannot be altered once the process has started. This is to ensure data integrity and consistency during the migration. Incorrect Process Flow: The error may arise if the user attempts to change the execution order or rules after the migration process has already begun or if the step is locked due to dependencies on previous steps. User Permissions: The user may not have the necessary permissions to change execution rules, leading to this error.
Solution: Check Process Status: Ensure that the migration
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