SMTP with Office 365 - TLS


I’ve always had issues with SMTP settings, configured to use my Office365 account. It seems to be pot luck if it works or not, however it’s been getting worse. I therefore have a few enhancement suggestions for you:

  1. Implement TLS / add tick box for TLS. I don’t know what your backend mail system is, but SSL 3.0 is not good. See here: TLS v SSL.

  2. I doubt it is actually a time out issue, but adding a time out
    variable might help. I constantly get:
    The operation has timed out. Your SMTP server did not reply in a timely fashion. Please ensure the port number is correct and any firewall on the SMTP server is allowing outside access.

  3. Where ever there is an option to email, implement a test function, so that one does not have to create test invoices to see if the email comes out as expected, especially when “some html” is “allowed”.

  4. When the option to send an email such as invoices or payment notifications is selected, if the email does not send, do not log the payment or add a resend feature. When the email fails, I have to go in and delete the payment in order to resend.

I use Office365 SMTP in several other applications, and I don’t have issues. Even telnet and PowerShell tests always work. Tonight, I have change the SMTP settings over to gmail who support SSL & TLS, but I am getting the timeout issue with them.

These features would greatly speed up and simplify the process in getting corporate branding right.



I moved a post to a new topic: Manual Bank Feed - Barclays

NOTE: Read my edit further down first.

There’s a similar discussion regarding Office 365 and TLS here:

The .NET framework AFAIK doesn’t explicitly support TLS but setting the property enableSsl will allow for TLS communications (see here), this is something we’re already doing and can be invoked with the “use SSL” checkbox.

I’m not sure if other users have managed to configure Office 365 emails on QuickFile but any feedback would be welcome here.


OK this is nothing to do with SSL/TLS, I did suspect something else was going on here as if it were an authentication issue it would return an invalid authentication message, not a timeout.

As it happens it appears to be a case of IP blocking. We can actually connect to Office 365 SMTP on our local development environment but not in production. I will have a look to see where on Office 365 you can white list IPs. If you want to try this yourself it’s