diff --git a/tests/run-tests b/tests/run-tests
index 20fe1a541a..cc1020e60a 100755
--- a/tests/run-tests
+++ b/tests/run-tests
@@ -42,6 +42,12 @@ def run_tests(pyb, tests, args):
     if pyb is None and platform.architecture()[0] == '64bit':
         pass
 
+    # Some tests use unsupported features on Windows
+    if os.name == 'nt':
+        skip_tests.add('extmod\\ujson_loads.py') #works but -2e-3 is printed as -0.002000000000000001 except for mingw-w64
+        skip_tests.add('import\\import_file.py') #works but CPython prints forward slashes
+        skip_tests.add('unix\\ffi_float.py')
+
     # Some tests are known to fail with native emitter
     # Remove them from the below when they work
     if args.emit == 'native':
diff --git a/windows/mpconfigport.h b/windows/mpconfigport.h
index 9725c3dfe5..9e666e3f32 100644
--- a/windows/mpconfigport.h
+++ b/windows/mpconfigport.h
@@ -46,7 +46,7 @@
 #define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_MPZ)
 #define MICROPY_STREAMS_NON_BLOCK   (1)
 #define MICROPY_OPT_COMPUTED_GOTO   (0)
-#define MICROPY_PY_BUILTINS_STR_UNICODE (0)
+#define MICROPY_PY_BUILTINS_STR_UNICODE (1)
 #define MICROPY_PY_BUILTINS_FROZENSET (1)
 #define MICROPY_PY_SYS_EXIT         (1)
 #define MICROPY_PY_SYS_PLATFORM     "win32"