Tools > Options > Global > Integration

Note: These options are only available when Silk Test Workbench is integrated with eCATT.
RFC Trace
Set to On to enable diagnostic tracing of Silk Test Workbench RFC calls. The diagnostic traces are saved in a trace file.
Note: RFC is an SAP API implemented in an SAP .dll called librfc32.dll The trace file is created by code in this .dll, which also sets the location to store the trace file. The default location is the system folder.

Set a Windows environment variable for the path that you want RFC trace files to be dumped to. The variable is RFC_TRACE_DIR and its value should be the path. This is documented in the RFCSDK help provided by SAP.