diff --git a/dlls/user32/tests/class.c b/dlls/user32/tests/class.c
index d3c173a4ad0..a8475295880 100644
--- a/dlls/user32/tests/class.c
+++ b/dlls/user32/tests/class.c
@@ -542,7 +542,9 @@ static void test_instances(void)
     ok( !UnregisterClass( "BUTTON", (HINSTANCE)0x87654321 ), "Unregistered button a second time\n" );
     ok( GetLastError() == ERROR_CLASS_DOES_NOT_EXIST, "Wrong error code %d\n", GetLastError() );
     ok( !GetClassInfo( 0, "BUTTON", &wc ), "Button still exists\n" );
-    ok( GetLastError() == ERROR_CLASS_DOES_NOT_EXIST, "Wrong error code %d\n", GetLastError() );
+    ok( GetLastError() == ERROR_CLASS_DOES_NOT_EXIST ||
+        GetLastError() == ERROR_INVALID_PARAMETER /* W2K3 */,
+        "Wrong error code %d\n", GetLastError() );
 
     /* we can change the instance of a system class */
     check_instance( "EDIT", (HINSTANCE)0xdeadbeef, (HINSTANCE)0xdeadbeef, user32 );