system.net.mail does not send mail

Question

i am developing with vb2005, using system.net.mail to send mail using google configuration. a full sample of my code was posted here earlier

        With smtp
            .Host = "smtp.google.com"
            .Port = 465
            .UseDefaultCredentials = False
            .Credentials = New System.Net.NetworkCredential(mygoogleemail, mypass)
            .EnableSsl = true
            .Timeout = 60000
        End With

i get the operation has timed out. if i change the port to 587, it says that the server does not support secure connection

[EDIT] could firewall be blocking it?

is there anyway to specify sending application name?

Google will not let you use its SMTP server to send spam. Increase the timeout to at least 5 minutes. Try the gmail.com host. — Hans Passant, Mar 13 '11 at 14:45
@Hans Passant am just testing my app with 1 email only, and it dose not send — Smith, Mar 13 '11 at 15:42

score 2 · Answer 1 · edited May 23 '17 at 12:02

2

Have you tried the answer at : Sending email through Gmail SMTP server with C#

Just to see if that works.

Note that in the answer to his solution he mentions web.config changes lower in the post not accepted as the answer

<system.net>
  <mailSettings>
    <smtp from="myusername@gmail.com" deliveryMethod="Network">
      <network defaultCredentials="false" enableSsl="true" host="smtp.gmail.com" port="587" password="password" userName="myusername@gmail.com"/>
    </smtp>
  </mailSettings>  
</system.net>

edited May 23 '17 at 12:02

Community

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1

answered Mar 13 '11 at 13:51

sclarson

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is there any difference in what i have done here and what is done in the link you posted? – Smith Mar 13 '11 at 14:21
Yes, he mentioned web.config changes that had to be made. – sclarson Mar 13 '11 at 15:05
am not developing a web app, instead a desktop app – Smith Mar 13 '11 at 15:44
If thats the case there should be appsettings.config or program.exe.config – sclarson Mar 13 '11 at 16:47

score 2 · Accepted Answer · answered Mar 13 '11 at 16:28

2

Try

Dim myLogin As New NetworkCredential("username@gmail.com", "password")
Dim msg As New MailMessage("username@gmail.com", "to@somedomain.com", "subjectLine", "emailBodyText")

msg.IsBodyHtml = True

Try
    Dim client As New SmtpClient("smtp.gmail.com", 587)
    client.EnableSsl = True
    client.UseDefaultCredentials = false
    client.Credentials = myLogin
    client.Send(msg)
Catch ex As SmtpException
    msgbox(ex.Message)
End Try

If you get the timeout then troubleshoot

Go to gmail.com and make sure you can loging with those credentials.
Login to gmail account and go to settings and make sure POP/IMAP is setup. I don't think they allow you to send mail thru your account unless this is turned on.
Try changing the port to 25 with SSL.
Try to TELNET the mail server to see if you are able to send relay mails via your ISP

Open command prompt and type (without quotes) telnet smtp.gmail.com 25

If you get a timeout then the problem is either your local LAN is blocking mails or your ISP.

answered Mar 13 '11 at 16:28

Saif Khan

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I can telnet to google at 587, but when i use my app, it says the operation has timedout – Smith Mar 13 '11 at 18:30
Then the problem must be in the GMail account setup. Try using an email client like Outlook and setup an account with the same credentials and see if you are able to send emails. – Saif Khan Mar 15 '11 at 03:15
actually, i just used another smtp server, and it worked. i don't know what is wrong with google – Smith Mar 16 '11 at 14:02
Ha! Then your gmail account is not properly configured for access by another client (e.g. POP3) OR your "FROM" address does not match the username so the connection is dropped. – Saif Khan Mar 16 '11 at 19:12

score 1 · Answer 3 · answered Mar 13 '11 at 16:15

The port was right in the OP, but the host was wrong

    With smtp
        .Port = 465 '465 for ssl
        .EnableSsl = True
        .UseDefaultCredentials = False
        .Credentials = New System.Net.NetworkCredential("myusername@gmail.com", "yourpassword")
        .Host = "smtp.gmail.com"
    End With

And just to verify, you have pop enabled in gmail, correct?

score 0 · Answer 4 · edited Nov 22 '13 at 19:03

If you are using TWO STEP VERIFICATION for gmail, then disable it first and then try again with this code

Dim myLogin As New NetworkCredential("username@gmail.com", "password")
Dim msg As New MailMessage("username@gmail.com", "to@somedomain.com", "subjectLine", "emailBodyText")

msg.IsBodyHtml = True

Try
    Dim client As New SmtpClient("smtp.gmail.com", 587)
    client.EnableSsl = True
    client.UseDefaultCredentials = false
    client.Credentials = myLogin
    client.Send(msg)
Catch ex As SmtpException
    msgbox(ex.Message)
End Try

score -1 · Answer 5 · edited May 23 '17 at 12:26

-1

The Port number is 587.

And also, try this order as per this solution

    With smtp
        .UseDefaultCredentials = False
        .Credentials = New System.Net.NetworkCredential("myusername@gmail.com", "mypwd")
        .Host = "smtp.gmail.com"
        .Port = 587
        .EnableSsl = true
    End With

edited May 23 '17 at 12:26

Community

1
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answered Mar 13 '11 at 13:55

naveen

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i still get the same error `the server does not support secure connection` – Smith Mar 13 '11 at 14:03
@smith: can you post the exact code you are using. i dont see smtp.google.com enclosed in double quotes – naveen Mar 13 '11 at 15:12

system.net.mail does not send mail

5 Answers5