Since Anaconda stores the Python environment in a different location than an original distribution, the PATH environment variable will need to be configured. You will need to add the path to Python and scripts folder from the installation you want to use. If you installed Anacoda with Python 3.7 for your user, then you will need to add the following two paths to the PATH environment variable:
C:\Users\<Username>\AppData\Local\Continuum\anaconda3
C:\Users\<Username>\AppData\Local\Continuum\anaconda3\Scripts
Also, you will need to add two new user variables:
PYTHONHOME => C:\ProgramData\Anaconda3
PYTHONPATH => C:\ProgramData\Anaconda3\Lib
You will need to close out of TestStand and the TestStand Version Selector for the Python version to appear in the Python Adapter configuration window.
You can follow the KnowledgeBase article
Editing the PATH Environment Variable for TestStand’s Python Adapter to do this.