The you're connecting to (e.g., PowerMill, SolidWorks). The file formats you need to convert (e.g., .stp to .dgk). Any error messages you're currently encountering.
Delcam PS Exchange 3407 appears to be a tool or module designed to facilitate this process. Although specific details about version 3407 are scarce, Delcam's PS Exchange software is generally used to enable the smooth transfer of data between various CAD formats. delcam ps exchange 3407 link