Send email with attachment through windows application

Imports System.Net
Imports System.Net.Mail

 1. Using your Gmail Account

Dim MyMailMessage As New System.Net.Mail.MailMessage(Sender's email address, Receiver's email address, Subject, msg)
MyMailMessage.IsBodyHtml = False
Dim attach As New System.Net.Mail.Attachment(path of filename)
MyMailMessage.Attachments.Add(attach)
Dim mailAuthentication As New NetworkCredential(Sender's email Address, Sender's Password)
Dim mailClient As New System.Net.Mail.SmtpClient("smtp.gmail.com", 587)
mailClient.EnableSsl = True
mailClient.UseDefaultCredentials = False
mailClient.Credentials = mailAuthentication
mailClient.Send(MyMailMessage)
MyMailMessage.Attachments.Dispose()

2. From your yahoo Account

Replace the following lines on the above code

Dim mailClient As New System.Net.Mail.SmtpClient("smtp.gmail.com", 587)
mailClient.EnableSsl = True

with

Dim mailClient As New System.Net.Mail.SmtpClient("smtp.mail.yahoo.com", 25)
mailClient.EnableSsl = False