Vb.net – cant login website using httpwebrequest/responce vb.net

I am a newb to vb.net(visual studio 2008).i am trying to make an app using vb.net which can be used to login to a website and browse that website without using webbrowser(i dont want to use webbrowser of vb.net).i got a code for this from net ;I have made a temporary login webpage using php and mysql in my computer(its working properly).
but when i tried to login using vb.net its not working…
because i dont know in which part of the code is not working,i am pasting the whole code here.

below is my html code for login form

    <td style="width: 188px;"><input maxlength="120" size="30" name="login" class="css"  id="login"><br>
<br>
</td>
</tr>
<tr>

<td><b>Password</b></td>
<td><input maxlength="100" size="30" name="password" class="css" id="password" type="password"><br>
<br>
</td>
</tr>
<tr>
<td>&nbsp;</td>
<td><input name="submit" value="Login" class="button" type="submit"></td>

this is the vb.net code that i got it from net.i changed the url to my localhost website..and added username and password(both root) and also this <big>Welcome

Imports System.Net
Imports System.Text
Imports System.IO

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim cookieJar As New Net.CookieContainer()
        Dim request As Net.HttpWebRequest
        Dim response As Net.HttpWebResponse
        Dim strURL As String

        Try
            'Get Cookies
            strURL = "http://localhost/login.php"
            request = Net.HttpWebRequest.Create(strURL)
            request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3"
            request.Method = "GET"
            request.CookieContainer = cookieJar
            response = request.GetResponse()

            For Each tempCookie As Net.Cookie In response.Cookies
                cookieJar.Add(tempCookie)
            Next

            'Send the post data now
            request = Net.HttpWebRequest.Create(strURL)
            request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3"
            request.Method = "POST"
            request.AllowAutoRedirect = True
            request.CookieContainer = cookieJar

            Dim writer As StreamWriter = New StreamWriter(request.GetRequestStream())
            writer.Write("login=root & password=root")
            writer.Close()
            response = request.GetResponse()

            'Get the data from the page
            Dim stream As StreamReader = New StreamReader(response.GetResponseStream())
            Dim data As String = stream.ReadToEnd()
            RichTextBox1.Text = data
            WebBrowser1.DocumentText = RichTextBox1.Text
            response.Close()

            If data.Contains("<big>Welcome") = True Then
                'LOGGED IN SUCCESSFULLY
            End If

        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Sub
End Class

Thanks for your help