SP Doesn't Return Value In Tableadabter

Hi all,

When I execute a stored procedure that returns a single value using a TableAdapter, I always get error message "Object reference not set to an instance of an object"

I followed all the steps in microsoft help center:
http://msdn2.microsoft.com/en-us/library/37hwc7kt.aspx

but the problem still unsolved.

here are my simple stored procedure:
create PROCEDURE dbo.StoredProcedure1

AS
RETURN 4


and here are the simple code in my asp.net webpage that should display the number "4": protected void Button1_Click(object sender, EventArgs e)
{
DataSet1TableAdapters.QueriesTableAdapter TA
= new DataSet1TableAdapters.QueriesTableAdapter();
int i = (int) TA.StoredProcedure1();
Response.Write(i.ToString());

}


so, please could any one help me solve this problem?