Nuitka cant unset WIN 32 build option : CPPDEFINE for _WIN32_WINNT=0x0601

Question

Running W10 pro X64, python 3.12.3, nuitka 2.6.7

Recently in a hurry I tried many things to build a WIN32 exe using nuitka, never successful, even though I was previously building x64 exe's without issue.

Having reverted to building X64 exe's now the resulting exe fails to run. Tried building from existing python files that worked previously and with identical Nuitka command line options and it also fails to run. The only difference I can find is that the failing builds are being compiled with different options.

Looking at the scons-report.txt from earlier successful builds and comparing with the current failing builds I can see that there is now an additional '_WIN32_WINNT=0x0601' option in the CPPDEFINES array in the failing builds scons-report :

CPPDEFINES=['_WIN32_WINNT=0x0601', '__NUITKA_NO_ASSERT__', '_NUITKA_WINMAIN_ENTRY_POINT', '_NUITKA_STANDALONE', '_NUITKA_ONEFILE_MODE', '_NUITKA_ONEFILE_TEMP_BOOL', '_NUITKA_CONSTANTS_FROM_RESOURCE', '_NUITKA_FROZEN=153', '_NUITKA_EXE', '_NUITKA_PLUGIN_MULTIPROCESSING_ENABLED=1']

I probably wrongly/unknowingly issued some command line statement that forced this change but I can't remember what, and in any case how do I 'undo' this option?

From research CPPDEFINES is the C pre-processor command line, and Nuitka is using the Version C compiler: C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\VC\Tools\MSVC\14.41.34120\bin\Hostx64\x64\cl.exe (cl 14.3).

Thanks in advance for any ideas/suggestions/insight

I a have tried forcing Nuitka reinstall, and repairing the C++ installations with no change