TaskPane in Excel UI Problem

Hi All,

I have created a user control for using it in MS Excel TaskPane. It was working perfectly( until today on a particular client). It should have been like this: 

But instead its looking like this on a client side:

Notice that combo box some part s hidden in this picture. and when tree view's data load into it, scroll bar is also hidden. Any idea?

Thanks,

Attiqe

Attiqe Ur Rehman