SendGrid works in development but not production

I am using NOP Commerce on the Azure platform, I have integrated an new module that sends an email to the merchant. The from email is the same as the domain but the merchant wants to receive it via their .aol.com account. Everything works fine in development and in local compiled releases using http://localhost however when published to the production environment the emails are not being sent. In fact they are not even appearing on the SendGrid email activity screen.

Any ideas?

It might be that Azure stops outbound traffic on particular ports to prevent spamming.  SendGrid recommend port 587.

https://sendgrid.com/docs/Classroom/Basics/smtp_ports.html

I'm not sure if you're trying to use SSL - but it could also be that the SSL cipher demanded by SendGrid isn't installed on Azure instances as they've proven to be insecure (SHA1 hashes etc).  It seems unlikely, but try (testing) it with non-secure emails.

The nopCommerce logs might help steer you onto the issue also.

Figured this one out with some detail debugging. I was being a bit dim and did not migrate my template to the live server. Unfortunate NOP Commerce does not return an error message for this so took a while to work it out.