The 16.10 release can co-exist with the 15.10.10.00 release and later versions. The active release will be the last release installed. For example, if 15.10.10.00 is installed then 15.10.10.00 is the active release. Now, if 16.10 is installed after installing 15.10.10.00, then 16.10 will become the active release. The releases can be installed in any order. Installing 16.10 then 15.10.10.00 makes 15.10.10.00 the active release.
An application named "ListProducts" is located in the "Teradata Client 16.00" folder under Applications. ListProducts can be used to list the products installed and also change the active version. The difference between the active release and non-active release is that the bin folder will be on PATH. The "Install Configuration File" section indicates how to change the default behavior.
The notion of an active release will not apply when our software is installed on a shared location. See Third-Party .ENV Files for a description of how to access a particular release.