Magix bought Sony Creative Software, including Vegas a few years ago. There is no Sony Vegas 14, 15, 16, or 17, only Magix Vegas. The first version put out by Magix was Vegas 13. Anyone selling a "Sony Vegas 17" should be avoided and considered as a fraudster.
Eric gave you the link to the Sticky - look at the first part of this forum for the post in capital letters "VEGAS PRODUCTS FORUM" that has a link in it to the Vegas forum.
I’m curious why VEGAS is not included as one of the tabs under VIDEO, instead of appearing under MEP, VPX, etc? A simple step by Magix to minimise this frequent issue.