Message type: E = Error
Message class:  CNV - Conversion: Messages for Conversion Services (CNCC) 
Message number: 164
Message text: For table &1, there are steps during timestep AR (no drop-ins. tech.)
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message CNV164 typically relates to issues encountered during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. The message indicates that there are steps in the migration process that cannot be executed due to the presence of "drop-ins" or other technical constraints.
Cause: The error message CNV164 for table &1 indicates that during the migration process, there are certain steps that cannot be executed because they are not allowed in the current context. This could be due to: Data Integrity Issues: There may be data integrity constraints that prevent the migration from proceeding. Technical Restrictions: The migration process may have specific technical restrictions that prevent certain operations from being performed.
Configuration Issues: The configuration of the migration cockpit or the source system may not be set up correctly, leading to this error. Missing Dependencies: There may be missing dependencies or prerequisites that need to be fulfilled
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