正常Python加载.dll模块失败但Anaconda可运行的问题求助

我尝试用Python的ctypes包导入本地DLL，代码如下：

import ctypes
example_dll = ctypes.windll.LoadLibrary(".\\Example.dll")

该DLL依赖另外两个DLL，已放在同一目录下。代码在Anaconda（Python 3.7）环境中可正常运行，但在常规Python 3.10中运行时抛出错误：

FileNotFoundError: Could not find module: '...\Example.dll' (or one of its dependencies) Try using the full path with constructor syntax.

已尝试的排查方案 #

• 使用DLL完整路径加载，无效
• 通过Dependency Walker、dumpbin确认所有依赖DLL均存在，且DLL与Python 3.10均为64位
• 安装与Anaconda同版本的常规Python 3.7，问题未解决
• 调用os.add_dll_directory()指定DLL所在完整路径，无效
• 改用ctypes.CDLL()加载，仍失败

ctypes代码差异对比 #

对比Anaconda与常规Python的ctypes.__init__.py中CDLL类的winmode相关代码，发现常规Python缺少Anaconda中的一段逻辑：

Anaconda 版本代码 #

if _os.name == "nt":
    if winmode is not None:
        mode = winmode
    else:
        import nt
        mode = nt._LOAD_LIBRARY_SEARCH_DEFAULT_DIRS
        if '/' in name or '\\' in name:
            self._name = nt._getfullpathname(self._name)
            mode |= nt._LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR
        # PATH is how DLL lookup has always worked in the past
        # in Python on Windows. IMHO both the above mode flags
        # are not wanted and cause many serious regressions within
        # the conda ecosystem on Windows. We should however
        # propagate any PATH changes that have happened to Python
        # library and that is not yet implemented.
        LOAD_WITH_ALTERED_SEARCH_PATH = 0x00000008
        mode = LOAD_WITH_ALTERED_SEARCH_PATH

常规Python 3.10 版本代码 #

if _os.name == "nt":
    if winmode is not None:
        mode = winmode
    else:
        import nt
        mode = nt._LOAD_LIBRARY_SEARCH_DEFAULT_DIRS
        if '/' in name or '\\' in name:
            self._name = nt._getfullpathname(self._name)
            mode |= nt._LOAD_LIBRARY_SEARCH_DLL_LOAD_DIR

将Anaconda中缺失的代码添加到常规Python后，运行抛出新错误：

OSError: [WinError 193] %1 is not a valid Win32 application

该错误通常与32/64位不兼容相关，但已确认所有组件均为64位。

疑问：这是否是Python的bug？为何仅Anaconda环境可正常运行？求解决思路。

注：Example.dll的最后两个依赖为专有DLL，已放置在同一目录，调试发现问题出在Example.dll本身。

内容的提问来源于stack exchange，提问作者Siron