The Python website, https://wiki.python.org/moin/WindowsCompilers, says we should be able to use the MSVC 2017 as long as setuptools is version 34.4.0 or higher. MSVC 2015 is hard to come by now. I am trying a reinstall now to see if it helps. The alternative solution is also difficult to figure out since I don't have a mincore.lib file. Kevin