[Solved] Email not sending in ASP.Net using VB.Net

hello,

last time you sent me the step by step how to grap the username from the server and send it to the email.

i had made some change to fit in with my department and the server, but then when i click the button, then it's said send sucessfully, but i don't recieve anything.

i will show you two version

this is your version from last time.

Protected Sub SendEmail(ByVal sender As Object, ByVal e As EventArgs)
    Dim username As String = String.Empty
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("SELECT Username FROM Users WHERE Email = @Email")
            cmd.Parameters.AddWithValue("@Email", txtEmail.Text.Trim())
            cmd.Connection = con
            con.Open()
            Using sdr As SqlDataReader = cmd.ExecuteReader()
                If sdr.Read() Then
                    username = sdr("Username").ToString()
                End If
            End Using
            con.Close()
        End Using
    End Using
 
    If Not String.IsNullOrEmpty(username) Then
        Dim mm As MailMessage = New MailMessage("sender@gmail.com", txtEmail.Text.Trim())
        mm.Subject = "Username Recovery"
        mm.Body = String.Format("Your Username is {0}.<br /><br />Thank You.", username)
        mm.IsBodyHtml = True
        Dim smtp As SmtpClient = New SmtpClient()
        smtp.Host = "smtp.gmail.com"
        smtp.EnableSsl = True
        Dim NetworkCred As NetworkCredential = New NetworkCredential()
        NetworkCred.UserName = "sender@gmail.com"
        NetworkCred.Password = "<Password>"
        smtp.UseDefaultCredentials = True
        smtp.Credentials = NetworkCred
        smtp.Port = 587
        lblMessage.ForeColor = Color.Green
        lblMessage.Text = "Username has been sent to your email address."
    Else
        lblMessage.ForeColor = Color.Red
        lblMessage.Text = "This email address does not match our records."
    End If
End Sub

this is my version:  please help me to rewrite it if you see any error because i did not recieve any email after i click the button.

Protected Sub SendEmail(ByVal sender As Object, ByVal e As EventArgs)
    Dim username As String = String.Empty
    Dim constr As String = ConfigurationManager.ConnectionStrings("DBHUSRConnectionString").ConnectionString
    Using con As SqlConnection = New SqlConnection(constr)
        Using cmd As SqlCommand = New SqlCommand("SELECT aspnet_Users.UserName, aspnet_Membership.Email FROM aspnet_Users INNER JOIN aspnet_Membership ON aspnet_Users.UserId = aspnet_Membership.UserId WHERE aspnet_Membership.Email = @Email")
 
            cmd.Parameters.AddWithValue("@Email", txtEmail.Text.Trim())
            cmd.Connection = con
            con.Open()
            Using sdr As SqlDataReader = cmd.ExecuteReader()
                If sdr.Read() Then
                    username = sdr("Username").ToString()
                End If
            End Using
            con.Close()
        End Using
    End Using
 
    If Not String.IsNullOrEmpty(username) Then
        Dim mm As MailMessage = New MailMessage("sender@fullerton.edu", txtEmail.Text.Trim())
        Dim toAddress As String = txtEmail.Text
 
        mm.Subject = "Username Recovery"
        mm.Body = String.Format("Your Username is {0}.<br /><br />Thank You.", username)
        mm.IsBodyHtml = True
 
        Dim smtp As SmtpClient = New SmtpClient()
        smtp.Host = "smtp.fullerton.edu"
        smtp.EnableSsl = True
        Dim NetworkCred As NetworkCredential = New NetworkCredential()
        NetworkCred.UserName = "sender@fullerton.edu"
        NetworkCred.Password = "<Password>"
        smtp.UseDefaultCredentials = True
        smtp.Credentials = NetworkCred
        smtp.Port = 587
        lblMessage.ForeColor = Color.Green
        lblMessage.Text = "Username has been sent to your email address."
    Else
        lblMessage.ForeColor = Color.Red
        lblMessage.Text = "This email address does not match our records."
    End If
End Sub

thanks