Auto-Tune EFX+ (version 9.x.x) is the compatible upgrade to Auto-Tune EFX 3. This means the Auto-Tune EFX+ installation replaces previous installations of Auto-Tune EFX 3, and Auto-Tune EFX+ will successfully load Auto-Tune EFX 3 settings and automation data saved in your project files.
Important: Even though Auto-Tune EFX+ (v9.x.x) can load settings saved with Auto-Tune EFX 3, Auto-Tune EFX 3 cannot load settings saved with Auto-Tune EFX+ (i.e. Auto-Tune EFX+ is backward compatible with Auto-Tune EFX 3, but Auto-Tune EFX 3 is not forward compatible with Auto-Tune EFX+).
Recommended tip: If you wish to keep original backup copies of projects that used Auto-Tune EFX 3, be sure to “Save As…” these project files to create a copy before or immediately after installing Auto-Tune EFX+. Doing this will allow you to keep an original copy of your work with Auto-Tune EFX 3 in case you need to access it later with Auto-Tune EFX 3 instead of Auto-Tune EFX+.