diff --git a/pjlib/src/pj/ioqueue_winnt.c b/pjlib/src/pj/ioqueue_winnt.c
index afb75c5..32a7466 100644
--- a/pjlib/src/pj/ioqueue_winnt.c
+++ b/pjlib/src/pj/ioqueue_winnt.c
@@ -33,9 +33,9 @@
     WSAOVERLAPPED	   overlapped;
     pj_ioqueue_operation_e operation;
 } generic_overlapped;
-
+
 /*
- * OVERLAP structure for send and receive.
+ * OVERLAPPPED structure for send and receive.
  */
 typedef struct ioqueue_overlapped
 {
@@ -74,6 +74,14 @@
     ioqueue_accept_rec      accept;
 #endif
 };
+
+/* Type of handle in the key. */
+enum handle_type
+{
+    HND_IS_UNKNOWN,
+    HND_IS_FILE,
+    HND_IS_SOCKET,
+};
 
 /*
  * Structure for individual socket.
@@ -82,7 +90,8 @@
 {
     pj_ioqueue_t       *ioqueue;
     HANDLE		hnd;
-    void	       *user_data;
+    void	       *user_data;
+    enum handle_type    hnd_type;
 #if PJ_HAS_TCP
     int			connecting;
 #endif
@@ -316,7 +325,8 @@
     /* Build the key for this socket. */
     rec = pj_pool_zalloc(pool, sizeof(pj_ioqueue_key_t));
     rec->ioqueue = ioqueue;
-    rec->hnd = (HANDLE)sock;
+    rec->hnd = (HANDLE)sock;
+    rec->hnd_type = HND_IS_SOCKET;
     rec->user_data = user_data;
     pj_memcpy(&rec->cb, cb, sizeof(pj_ioqueue_callback));
 
@@ -336,7 +346,7 @@
     *key = rec;
     return PJ_SUCCESS;
 }
-
+
 /*
  * pj_ioqueue_unregister()
  */
@@ -362,7 +372,10 @@
 	key->connecting = 0;
 	pj_lock_release(ioqueue->lock);
     }
-#endif
+#endif
+    if (key->hnd_type == HND_IS_FILE) {
+        CloseHandle(key->hnd);
+    }
     return PJ_SUCCESS;
 }
 
@@ -482,7 +495,7 @@
     }
     return -1;
 }
-
+
 /*
  * pj_ioqueue_recv()
  *
@@ -505,7 +518,7 @@
     union operation_key *op_key_rec;
 
     PJ_CHECK_STACK();
-    PJ_ASSERT_RETURN(key && op_key && buffer, PJ_EINVAL);
+    PJ_ASSERT_RETURN(key && op_key && buffer && length, PJ_EINVAL);
 
     op_key_rec = (union operation_key*)op_key->internal__;
     op_key_rec->overlapped.wsabuf.buf = buffer;