Message type: E = Error
Message class:  CNVMBTRFC - Messages used in RFC Management and its objects 
Message number: 088
Message text: Function module &1 returns with unknown error.
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The SAP error message CNVMBTRFC088 indicates that a function module has returned an unknown error during a remote function call (RFC). This error is often encountered in the context of data migration or conversion processes, particularly when using the SAP Landscape Transformation (SLT) or other data migration tools. Causes: Function Module Issues: The function module specified in the error message may have internal issues, such as coding errors, missing parameters, or incorrect logic. Data Issues: The data being processed may be inconsistent, incomplete, or not conforming to expected formats, leading to failures in the function module. Configuration Problems: Incorrect configuration settings in the RFC destination or the function module itself can lead to errors. Authorization Issues: The user executing the function may not have the necessary authorizations to perform the operation. System Resource Limitations: Insufficient memory or other system resources can cause function modules to fail unexpectedly. Network Issues: Problems with network connectivity between systems can lead
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