<P>当一个ActiveX控件和UpdatePane同时存在的时候。只要执行一个webcontrol的事件，就会报错。错误提示如下：</P> <H2><I>Invalid postback or callback argument. &nbsp;Event validation is enabled using &lt;pages enableEventValidation="true"/&gt; in configuration or &lt;%@ Page EnableEventValidation="true" %&gt; in a page. &nbsp;For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. &nbsp;If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.</I> </H2>