c# & InterOp & OptionButtons

[Timo]

Hello there,

Well, right know I'am really frustrated about Interop and Office. I wanted
to open an existing excel. Within I have some different controles. Some of
them shapes and some of them Optionbuttons.
When I opend my excel set reference to my workbook and to my sheet I wanted
to access my optionbuttons. Especially the values. It was not possible. I got
an cast error. I do not understand why.
It was possible to get all controls within a list and there names. Than I
casted to an Optionbutton. I got an error.
Know someone here how to access optionbuttons within excel in c#? Get the
values???

Regards
Timo