I have the following code to send email through SMTP:


Code:
 Private Sub SendMailToAdmin()
        Try
            RecipientAddress = ""
            Dim YesDate As String = Now.AddMonths(0).ToString("MMM yyyy")
            Dim oMsg As New MailMessage()
            oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate", 1)
            oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusername", SenderAddress)
            oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendpassword", SenderPassword)

            oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserver", MailServer)
            oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpconnectiontimeout", 10)
            ' oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusing", 2)
            oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserverport", 587)
            oMsg.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpusessl", True)


            oMsg.From = DisplayID
            oMsg.To = strEmailErrorTo
            oMsg.Cc = strEmailErrorCc
            oMsg.Subject = "Testing Email "

            oMsg.BodyFormat = MailFormat.Html

            oMsg.Body = "<HTML><HEAD><style>.Bd1 { FONT-SIZE: 10pt; COLOR: #000000; FONT-FAMILY: Verdana; TEXT-ALIGN: LEFT } "
            oMsg.Body &= "</style></HEAD><BODY class=Bd1>"
            oMsg.Body &= "Testing Email<br /><br />"
            oMsg.Body &= "</BODY></HTML>"

            SmtpMail.SmtpServer = MailServer
            SmtpMail.Send(oMsg)

            oMsg = Nothing
        Catch ex As Exception
            ErrorToAdmin("Billing: Failed To Send Out Testing Email " + ex.Message)
        End Try

    End Sub

I get the error when trying to send out email:

The transport failed to connect to the server.


Does anyone know the cause of it??