Shoutbox

I have a script that works perfectly in Windows XP, but does not work in Windows 7.
Here's the problem with the code.

code:

---

Interop.Call("User32.dll", "ShowWindow", ChatWnd.Handle, 0);

---

I'm using the event

code:

---

OnEvent_ChatWndReceiveMessage(ChatWnd, Origin, Message, MsgKind)

---

what should I do to make this function working again?