Application Role, App Role

 Hi all,
 I am trying to connect to the database using application role.  But gives an error
 An error has occurred while establishing a connection to the
server.  When connecting to SQL Server 2005, this failure may be caused by
the fact that under the default settings SQL Server does not allow remote
connections. (provider: SQL Network Interfaces, error: 26 - Error Locating
Server/Instance Specified)

 
for the given connection string
 Dim connstring
As String =
"Data Source=Northwind;Initial
Catalog=OrderProcessing;Persist Security Info=True;UserID=application_login;Password=wewewe;"


        Dim cmd
As SqlCommand


        Dim
param As SqlParameter


        Dim
cookie As Byte()


        Dim cn As New
SqlConnection(connstring)


        If
(cn.State = ConnectionState.Closed) Then


            cn.Open()


        End If Please help.. 


 
 Thanking you,
 
Nirmala