"Not user found !"

Hi. I am new in using vs2008. I have a problem with connection sql Databas. Pls help me
I have DB connection class file and connection string in web config. Database there is username,loginid and password. But once execute
system prompt "Not user found !" Pls help me.
 
dbconn.vb
Imports Microsoft.VisualBasic
Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration.ConfigurationManager
Imports System.Web.UI.Control
Imports System
Public Class dbconn
Public Shared strconn As String = AppSettings("ConnectString").ToString
Public Shared conn As New SqlConnection(strconn)
Public Shared Function OPEN() As Boolean
Try
If conn Is Nothing Then
conn = New SqlConnection(strconn)
conn.Open()
Else
If conn.State = ConnectionState.Closed Then
conn.Open()
End If
Return True
End If
Catch ex As Exc ...