The public properties and methods of an ActiveX control can only be referenced after the ActiveX control has been instantiated and initialized completely; otherwise the AxHost.InvalidActiveXStateException exception is thrown. The AxHost.InvalidActiveXStateException exception class contains the name of the member that made the reference and the member type. The member type is one of the AxHost.ActiveXInvokeKind enumerated values.
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AxHost.InvalidActiveXStateException Class[
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