diff --git a/src/impl/win.cc b/src/impl/win.cc
index c25bf4f..48bd699 100644
--- a/src/impl/win.cc
+++ b/src/impl/win.cc
@@ -242,6 +242,7 @@ Serial::SerialImpl::reconfigurePort ()
 
   // activate settings
   if (!SetCommState(fd_, &dcbSerialParams)){
+    CloseHandle(fd_);
     THROW (IOException, "Error setting serial port settings.");
   }