diff --git Modules/selectmodule.c Modules/selectmodule.c
index 6ea308a..02bc2ca 100644
--- Modules/selectmodule.c
+++ Modules/selectmodule.c
@@ -23,7 +23,7 @@
    FD_SETSIZE higher before this; e.g., via compiler /D switch.
 */
 #if defined(MS_WINDOWS) && !defined(FD_SETSIZE)
-#define FD_SETSIZE 512
+#define FD_SETSIZE 2048
 #endif
 
 #if defined(HAVE_POLL_H)
