diff --git a/setup.cfg b/setup.cfg
index 557e7c35..7de39f6b 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -25,7 +25,7 @@ classifier =
     Operating System :: POSIX
     Operating System :: Unix
     Operating System :: MacOS :: MacOS X
-    Operating System :: Windows
+    Operating System :: Microsoft :: Windows
     License :: OSI Approved :: MIT License
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3.9