wiiリモコンを使うためにWiimoteLibを使っているのですが、このエラーが出てよくわかりません

IOException: Invalid handle.
System.IO.FileStream..ctor (IntPtr handle, FileAccess access, Boolean ownsHandle, Int32 bufferSize, Boolean isAsync, Boolean noBuffering) (at /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.IO/FileStream.cs:97)
System.IO.FileStream..ctor (IntPtr handle, FileAccess access, Boolean ownsHandle, Int32 bufferSize, Boolean isAsync)
System.IO.FileStream..ctor (Microsoft.Win32.SafeHandles.SafeFileHandle handle, FileAccess access, Int32 bufferSize, Boolean isAsync)
(wrapper remoting-invoke-with-check) System.IO.FileStream:.ctor (Microsoft.Win32.SafeHandles.SafeFileHandle,System.IO.FileAccess,int,bool)
WiimoteLib.Wiimote.OpenWiimoteDeviceHandle (System.String devicePath)
WiimoteLib.Wiimote.WiimoteFound (System.String devicePath)
WiimoteLib.Wiimote.FindWiimote (WiimoteLib.WiimoteFoundDelegate wiimoteFound)
WiimoteLib.Wiimote.Connect ()
Wii.NewBehaviourScript.Update () (at Assets/NewBehaviourScript.cs:17)

対処法をお願いします。
使用OSはwindows7 64bit です