Upgrade from the old Asset Store version of Cinemachine
If you already installed a very old version of Cinemachine from the Unity Asset Store, you should upgrade to the Cinemachine Package.
Note
To upgrade from this version to the Cinemachine 3.x version, it is recommended to upgrade to Cinemachine 2.x first, which in most cases is completely automatic, and then from Cinemachine 2.x to Cinemachine 3.x.
Step 1: Upgrade to Cinemachine 2.x
To upgrade the Asset Store version to Cinemachine 2.x:
In Unity Editor, 2019.4+ or later, open your project.
Save the current Scene you are working on.
Create a new, empty Scene.
In the Project window, delete the Cinemachine Asset and any CinemachinePostProcessing adaptor assets you may have installed.
Install the Cinemachine 2.x package.
Step 2: Upgrade to Cinemachine 3.x
Once your project upgrade to Cinemachine 2.x is complete:
Minimally test your project to make sure it is functional with Cinemachine 2.x.
Follow the instructions to upgrade your project to Cinemachine 3.x.
Important
Read carefully all disclaimers about evaluating the necessity of this upgrade before you proceed.