Windows install complains Python isn't installed

[xobs]

After installing the latest release on Windows 10 (with all install options selected), running the program gives an error:

"Python Launcher is sorry to say...

Requested Python version (2.7) is not installed"

However, it is installed:

C:\Users\smcro>C:\Python27\python2
Python 2.7.16 (v2.7.16:413a49145e, Mar  4 2019, 01:37:19) [MSC v.1500 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
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