Hi,

I am using DNN v7.3.3 and integrating with SendGrid SMTP over port 465 for SSL connections. I had the following settings in DNN:

SMTP Server:  smtp.sendgrid.net:465
Connection Limit: 1
Max Idle Time: 0
Enable SSL: Yes
SMTP Authentication: Basic
SMTP Authentication Username / Password: (provided)

Running a test email did not go through and DNN had the following exception:

System.Net.Mail.SmtpException: The operation has timed out.
   at System.Net.Mail.SmtpClient.Send(MailMessage message)
   at DotNetNuke.Services.Mail.Mail.SendMailInternal(MailMessage mailMessage, String subject, String body, MailPriority priority, MailFormat bodyFormat, Encoding bodyEncoding, IEnumerable`1 attachments, String smtpServer, String smtpAuthentication, String smtpUsername, String smtpPassword, Boolean smtpEnableSSL)

 

Is DNN using .Net library System.Net.Mail to send email. Reading from MSDN the library only supports "Explicit SSL" not "Implicit SSL". 

Is it possible to use "Implicit SSL" in DNN? 

Thanks,

Kat

Hi,

Thank you for the suggestions! I've tried successfully the following server and port combinations to send emails:

smtp.sendgrid.net:587
smtp.sendgrid.net:25 (or without port)

It looks like using "colon" between server and port works for me. 

However, it did not work when I point to port 465. Sorry if I didn't explain myself well about the implicit SSL. Referring to MSDN, it seems that the SmtpClient class from System.Net.Mail only supports the SMTP Service Extension for Secure SMTP over Transport Layer Security as defined in RFC 3207.

Comparatively, an alternate connection method is where an SSL session is established up front before any protocol commands are sent. This connection method is sometimes called SMTP/SSL, SMTP over SSL, or SMTPS and by default uses port 465. This alternate connection method using SSL is not currently supported. (referring this alternate connection as implicit SSL)

Here is a link I found on MSDN with more details:

https://docs.microsoft.com/en-us/dotnet/api/system.net.mail.smtpclient.enablessl?view=netframework-4.7.2

Is it possible to use the alternate connection (implicit SSL) in DNN?

Thanks,

Kat

Thank you for the info! If this is something possible in DNN that'll be great! I have submitted a feature request on GitHub.