The SMTP bunch of code should be like this:
Dim smtpmail As System.Net.Mail.SmtpClient = New System.Net.Mail.SmtpClient("192.168.1.100", 25)
Dim credential As New System.Net.NetworkCredential("User Name", "Password")
smtpmail.UseDefaultCredentials = False
smtpmail.Credentials = credential
smtpmail.UseDefaultCredentials = True
smtpmail.Send(mm)
Thanks.