I'm new. So, hold on. This may be an inappropiate question but I don't know that. I have a friend that is working with me. He is not available for two more days. Any help would be greatly appreciated.

I am using 2008 Visual Studio.

This works:

<asp:DropDownList ID="StudentAdultDropDownList" DataSourceID="SqlDataSource3" runat="server" DataTextField="Student_Adult" DataValueField="Student_Adult" SelectedValue='<%# Bind("Student_Adult") %>' />
            <br />

This does not:

<asp:DropDownList ID="GuardianShipDropDownList" DataSourceID="SqlDataSource4" runat="server" DataTextField="GuardianShip" DataValueField="GuardianShip" SelectedValue='<%# Bind("GuardianShip") %>' />
            <br />

The error message is:
Server Error in '/' Application.
'GuardianshipDropDownList' has a SelectedValue that is invalid because it does not exist in the list of items.
Parameter name: value

The data source is a query. The names all match.

Can anybody help me?

>The data source is a query. The names all match.

How can you say that? - data source is a query.

You are assigning a value to the SelectedValue property of 'GuardianshipDropDownList' which is not available in GuardianshipDropDownList's Items collection.