VB .Net Sending email using Gmail account

问题:

Why does this timeout?

Dim s As New SmtpClient
s.Host = "smtp.gmail.com"
s.Port = 465
s.EnableSsl = True
s.Timeout = 5000
s.Credentials = New NetworkCredential("[e-mail]", "mypassword")

Dim m As New MailMessage
m.To.Add("[e-mail]")
m.From = New MailAddress("[e-mail]")
m.Body = "Test Message"
m.Subject = "Test Subject"
s.Send(m)

These settings come straight from my Outlook Express test setup, and it can send fine.

Set really long timeout = does nothing

Change port numbers to 587 or 25 = does nothing

One thought: Outlook Express has a "My server requires authentication" option, which I couldn't see an obvious equivalent for with SmtpClient. Could it be related to that?

Thanks in advance

Dave

--Trindaz on Fedang #vb.net-smtp

回答1:

Edit: You might need to add the following line: s.UseDefaultCredentials = False before the line starting with s.Credentials...

Do you have a firewall or some kind of anti-virus program running that might be blocking the connections?

A good place to start is to just do a simple connect from the command line.

telnet smtp.gmail.com 465

Note, depending on Windows version you might have to enable the telnet client first, see this link for details.

回答2:

You have to go into your gmail account and turn on access for less secure apps and change the port to 587