How To Fix DMC_GENERAL478 - Field &3 in Table &1 has unknown datatype &4 (RFC dest &2)

SAP Error Message - Details

• Message type: E = Error

• Message class: DMC_GENERAL - MWB: General Messages

• Message number: 478

• Message text: Field &3 in Table &1 has unknown datatype &4 (RFC dest &2)

Self-Explanatory Message

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.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message DMC_GENERAL478 - Field &3 in Table &1 has unknown datatype &4 (RFC dest &2) ?

  The SAP error message DMC_GENERAL478 indicates that there is an issue with a field in a specific table that has an unknown datatype. This error typically arises in the context of data migration or data transfer processes, particularly when using the Data Migration Cockpit (DMC) or similar tools.
  
  Cause:
  
  
  Unknown Datatype: The field in the specified table has a datatype that is not recognized by the system. This could be due to:
  
  A custom field or table that has not been properly defined in the system.
  A mismatch between the source and target systems, where the source system has a datatype that does not exist in the target system.
  An issue with the RFC (Remote Function Call) destination configuration, which may not be able to interpret the datatype correctly.
  
  
  
  Data Model Changes: If there have been recent changes to the data model (e.g., new fields added, datatypes changed), the DMC may not be aware of these