Open email before sending issue

We are using D365FO and have the Docentric AX Version 3.3.7.0 FREE installed. We are very happy with the product, but have been struggling with one problem, which we cannot resolve.
We have had contact with Microsoft support, but on analysis they have said that this is a Docentric issue.

Initially we were using Exchange, but we had the recommendation from Microsoft to use SMTP for sending emails. Unfortunately, we’re having the same problem with both and have tried various settings. Maybe you could give us some advice please?

We have a Docentric setup to send out an email from our shop and the problem only occurs when we have the Open email before sending set to ON. Otherwise it works.

We often have to add details to the email and therefore it is important for our users to be able to open, edit, then send. The response is the following:

00 error message

The email looks as follows:

02 outlook open before sending

The strange thing is that when we open that email and re-select the SAME From address and send it, it works. Do you know what the problem could be?

We have changed all the settings on the mail server and all other tests to “send test emails” work.
Currently, we have the following setup parameters:

01 smtp settings

We look forward to hearing from you.

This is unfortunately a known problem. It occurs when you download the generated email which has a different sender than the default user in Outlook. Even if the default user in Outlook has credentials to send on behalf of the specified sender, as you have already discovered, the sending of the message fails.

The only workaround for the sending to be successful is to delete and reselect the same sender in Outlook.

We already investigated to see if there is something missed when generating the EML file that Outlook opens, but we have not found anything that could be done to prevent this. Apparently Outlook adds something internally when you reselect the sender, and then processes it without a problem.

Unfortunately, we cannot help you any further. Perhaps you can contact Microsoft support with our response and attach the EML file that was generated so that they can also review it and figure out the reason for this strange behaviour.

Thanks very much for the information. We’ll contact Microsoft support again and hope to be able to resolve this problem, as it is frustrating for the users.