Sending email through VB.NET

I have made a real simple email client that works. However, the email is sent but it just takes for ever to get delivered. Why is that? The exact same email sent to the same address through the same ISP servers when sent through Outlook is virtually instant.

When I try to send though the local SMTP service on WinXP I get "Error!! Could not access 'CD).Message' object"

My code is below...

TIA
Russ

VB Code:

Private Sub btnSend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSend.Click
        Dim email As New MailMessage
        If txtSmtpServer.Text <> "localhost" Then
            SmtpMail.SmtpServer = Trim(txtSmtpServer.Text)
        End If
 
        email.To = Trim(Me.txtTo.Text)
        email.From = Trim(Me.txtFrom.Text)
        email.Subject = Trim(Me.txtSubj.Text)
        email.Body = Trim(Me.txtBody.Text)
        email.BodyFormat = MailFormat.Text
        email.Priority = MailPriority.High
 
        Try
            SmtpMail.Send(email)
            MsgBox("Email Sent!!!", MsgBoxStyle.Information)
        Catch ex As Exception
            MsgBox("Error!!" + vbLf + ex.Message, MsgBoxStyle.Critical)
        End Try
    End Sub 'btnSend_Click