In Mastercam 2017 go to File and down to Convert and choose Migration Wizard.
Choose the Advanced option.
Choose to Migrate Shared MCAMX Files, Include Subfolders, and then continue.
(if the wrong Shared McamX# is set as the Source Folder, use the Browse button to find the right one)
Click on the box next to File Types to unselect all the file types and and select Control Definitions, Machine Definitions, and Post Files.
The next page shows what versions of Mastercam you can migrate.
The last Window gives you a break down of what is being migrated, where the files are coming from, where they are going, and what versions are being migrated.
This process can be used to Migrate other files, just choose the file type you want to migrate, for example, Tool Libraries, Wire Power Libraries, or Operation Libraries. It is just recommended to do the post processors by themselves.