Bindingsource error value does not fall within the expected range

I am trying to add BindingSource to my default.aspx. In properties w开发者_运维问答indow, when I click on triangle for datasource, a message box appears saying

Value does not fall within the expected range

Why is that? How can I set it? Thanks

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There is NO BindingSource when it comes to ASP.NET You can bind a object directly without BindingSource.

I have seen a lot of questions from you recently, and they all seem to revolve around the same issues. Have you have a look at any asp.net information? http://www.asp.net/web-pages