Message type: E = Error
Message class:  USMD6 - Messages for Data Transfer 
Message number: 012
Message text: Data transfer &1 already exists
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The SAP error message USMD6012 indicates that a data transfer with the specified identifier (represented by &1) already exists in the system. This error typically occurs in the context of SAP Master Data Governance (MDG) when trying to create or replicate a data transfer that has already been initiated or exists in the system.
Cause: Duplicate Data Transfer: The most common cause of this error is an attempt to create a new data transfer with an identifier that is already in use. This can happen if the same data transfer is being processed multiple times or if there was a previous attempt that did not complete successfully. System Configuration: There may be issues with the configuration of the data transfer process, leading to conflicts in identifiers. User Error: Users may inadvertently try to create a transfer that they believe is new, not realizing that it already exists.
Solution: Check Existing Transfers: Use transaction codes like MDG_MAT
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