If you own SampleTank 3 or Syntronik, you can point SampleTank 4 to those folders to access all your old sounds within the new interface.

Get the Windows installer from the IK Multimedia website and log in with your account.

40 GB (SE), 128 GB (Standard), or 640 GB (MAX v2) depending on your version. Format: VST 2, VST 3, or AAX. 2. Installation and Authorization

Click the Padlock icon (Authorize) in the Product Manager. You can also enable "automatic authorization" in the settings.