--- SConstruct
+++ SConstruct
@@ -209,9 +209,14 @@

 # add prefixes defines
 if 'NSIS_CONFIG_CONST_DATA_PATH' in defenv['NSIS_CPPDEFINES']:
+       # We do use NSIS_CONFIG_CONST_DATA_PATH, but we don't use the path defines below.
+       # Those paths would get included as wchar_t* in the binaries.
+       # Conda currently only supports char* replacements.
+       # If we leave them out, we also avoid binary prefix replacement overall.
+       pass
-       defenv.Append(NSIS_CPPDEFINES = [('PREFIX_CONF', '"%s"' % defenv.subst('$PREFIX_CONF'))])
-       defenv.Append(NSIS_CPPDEFINES = [('PREFIX_DATA', '"%s"' % defenv.subst('$PREFIX_DATA'))])
-       defenv.Append(NSIS_CPPDEFINES = [('PREFIX_DOC', '"%s"' % defenv.subst('$PREFIX_DOC'))])
+#      defenv.Append(NSIS_CPPDEFINES = [('PREFIX_CONF', '"%s"' % defenv.subst('$PREFIX_CONF'))])
+#      defenv.Append(NSIS_CPPDEFINES = [('PREFIX_DATA', '"%s"' % defenv.subst('$PREFIX_DATA'))])
+#      defenv.Append(NSIS_CPPDEFINES = [('PREFIX_DOC', '"%s"' % defenv.subst('$PREFIX_DOC'))])
 
 if defenv.get('SOURCE_DATE_EPOCH','') is not '':
        defenv['ENV']['SOURCE_DATE_EPOCH'] = defenv['SOURCE_DATE_EPOCH'] = int(defenv['SOURCE_DATE_EPOCH'], 0) # Normalize and apply to ENV for child processes
--- Source/makenssi.cpp
+++ Source/makenssi.cpp
@@ -573,11 +573,7 @@
         tstring main_conf;
         TCHAR* env_var = _tgetenv(_T("NSISCONFDIR"));
         if (env_var == NULL)
-#ifndef NSIS_CONFIG_CONST_DATA_PATH
           main_conf = get_dir_name(get_executable_dir(argv[0]));
-#else
-          main_conf = _T(PREFIX_CONF);
-#endif
         else
           main_conf = env_var;
         main_conf += PLATFORM_PATH_SEPARATOR_STR;
--- Source/build.cpp
+++ Source/build.cpp
@@ -395,11 +395,7 @@
   const TCHAR *dir = _tgetenv(_T("NSISDIR"));
   if (dir) nsis_dir = dir;
   else {
-#ifndef NSIS_CONFIG_CONST_DATA_PATH
     nsis_dir = get_dir_name(get_executable_dir(makensis_path));
-#else
-    nsis_dir = _T(PREFIX_DATA);
-#endif
   }
   definedlist.add(_T("NSISDIR"), nsis_dir.c_str());