Yes, you can replace the default SMTP behavior in CMS 11 without relying on SendGrid.

In Optimizely CMS 11 (ASP.NET Framework), built-in messaging (forgot password, notifications, etc.) goes through the EPiServer mail abstraction. You can implement your own ISmtpClient (or override the mail service) and register it via DI.

This allows you to:

• Use OAuth2-based SMTP authentication

• Integrate with Microsoft Graph API instead of SMTP

• Route mail through an internal relay

As long as your custom implementation is registered in the container, the built-in messaging features will use it automatically.

The key is to replace the mail implementation - not just the <mailSettings> configuration. That’s typically the cleanest way to handle basic auth deprecation in CMS 11 environments.

Hi Jonas

Are you referring to the internal emails that the CMS sends out? Or the mails that the website sends out, as well?

In CMS 11, I believe you can create your own implementation of ISmtpClient. Sort of like the CMS 12 example I wrote about. But slightly different, as CMS 11 does not use MimeKit for emails.

Then you should be able to assign your implementation to the SmtpClientFactory.StaticFactory property. Or maybe you can intercept the SmtpClientFactory class with DI to set instanceFactory on creation.

Thanks @Keshav and @Stefan Intercepting SmtpClientFactory is the way I am after for having freedom for my own implementation. Thanks!

Great to hear, Jonas.

Since you are going to send mails through Outlook 365, I can recommend using the MS Graph SDK instead of SMTP. It is less "chatty" than SMTP this way.