My first embroidery machine was a Pfaff and came with the 4D software, if I remember correctly, the 4D Extra was an add on to the basic 4D package that was a separate charge. Upgraded to 5D that came out maybe 10 years or more ago and I was told by the Pfaff dealer that the 4D would no longer be supported because they were working on the 6D version which is current. The sad part of the HV/Pfaff support is that there was an annual fee of $129 sort of a membership if you will. That may no longer be true, I don't know, no longer have my embroidery machine.