1. Make sure you've downloaded the correct installer from the Korneff Audio site, for Windows it’s the .exe file, for Mac it’s the .pkg file, as well as updated to the most recent version of iLOK License Manager.
You can get your iLOK License Manager here.
2. Check if the plug-in is installed to the correct folder for your system.
For Mac OS, AAX plug-ins should be in the following folder:
» Macintosh HD:/Library/Application Support/Avid/Audio/Plug-Ins
For Windows, 64-bit AAX plug-ins should be in the following folder:
» C:\Program Files\Common Files\Avid\Audio\Plug-Ins
If you don’t find the respective files in the above folder, please reinstall your Korneff Audio plug-ins. If the plug-in files are there, you should perform a rescan. In order to do so, you need to delete certain files on your computer, depending on your Pro Tools version. Instructions available here.