Thanks for your report and research.
Obviously you are right. As I have to upgrade to support the newer features this has the drawback that somewhere in time old MSWindows versions are no longer supported. Unfortunately but that is as it is.
you find in the directories a file Build-Properties-64bits.txt which lists the environment used during build. That might be the easiest way to look for the last build version which runs on MSWindowsXP.
I have no older MSWindows versions so I can check this.
Date: Thu, 30 Jan 2020 18:03:35 +0100
Subject: PSPP-BUG: PSPP not compatible with Win XP anymore
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OS: Windows XP SP3 32-bit
Installation of pspp-20181109-daily-32bits-setup.exe (1.2.0) and pspp-20200117-daily-32bits-ForTestingOnly-setup.exe (1.3.0 nightly) works, but running of the PSPP application is not possible:
0.10.2-g654fff seems to install and run properly.
1.2.0 fails on startup: "dwmapi.dll" not found
1.3.0 nightly fails on startup: "GetFileInformationByHandleEx" not found in kernel32.dll
In both cases, deinstallation via uninstall.exe fails: Deletion of files starts regularly with expected speed, then after a few seconds slows down extremely to like 1-4 files per second, while un_a.exe causes a steady CPU load of 25 %. After killing the uninstall task, deletion of the remaining 950 files with Windows Explorer completes within 3 seconds.
As dwmapi.dll was propably introduced with Vista and GetFileInformationByHandleEx might have been changed in Vista, I assume that the incompatibility might be related to changes in the Win platform SDK used for compiling, or some constant/value is used which is not supported on WXP, cf. https://docs.microsoft.com/en-us/windows/win32/api/minwinbase/ne-minwinbase-file_info_by_handle_class
Thanks for looking into it. Cheers!