Where Is My Dynamically Created Controls?

Hi There.
I've Created A Dynamic Table And Controls Inside.
When I Want To Access My Dynamically Created Controls Forexample With This Line Of Code:

Response.Write(CType(FindControl("ddlHost1"), DropDownList).SelectedValue)

I Got An Object Reference Error.
Where Is My Controls And How To Access That?
Thanx in advance...

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