Express isn't designed to look in the folders Training Center puts things. As we have stopped developing Training Center, I would suggest uploading the data to Connect and sending to the device that way:
support.garmin.com/.../simpleCase.htm
Thanks for the support Albert. I have everything in Garmin Connect but from the website, if I transmit one workout or one course to 405CX then the others workouts/courses in 405CX deleted, I'm not interested. This is the only reason why I still use Training Center.