Message type: E = Error
Message class:  CNV20305 - Messages for conversion packages in CO 
Message number: 605
Message text: Problem in routine CNV_20305_ZUONR: Unknown parameter type
Routine CNV_20305_ZUONR is designed for converting intransparent fields
in field ZUONR.
For the dynamic call for field &V2& from table &V2&, a parameter type
&V3& has been specified. However the routine cannot process this
parameter type.
Additional information: The value of the field that is meant to be
converted is &V4&.
The routine cannot make the dynamic call; consequently, it cannot
convert the field either.
However the conversion is continued for the other fields and records.
Check if you really need to convert the given field; if yes, the
routine must be changed accordingly.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message CNV20305605, which indicates a problem in the routine CNV_20305_ZUONR due to an "Unknown parameter type," typically arises during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: Parameter Type Mismatch: The error suggests that the routine is encountering a parameter type that it does not recognize or that is not defined correctly. This could be due to: Incorrect data types being passed to the routine. Changes in the data structure or schema that the routine is not accounting for. Missing or misconfigured settings in the migration or conversion process. Custom Code Issues: If there are custom enhancements or modifications in the migration routines, they may not be compatible with the expected parameter types. Version Compatibility: The error may also arise if there are discrepancies between the versions of the source and target systems, or if the migration tool is not up to date.
Solution: Check Parameter Definitions:
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