We have a doucment library on Sharepoint 2013 that contains several email templates. These email templates are set to send from a specific shared mailbox. When you open up the email template from the sharepoint library the 'From' address correctly shows the shared mailbox name. However once the email is sent, the email shows in your 'Sent Items' folder and not the sent items folder of the shared mailbox.
This is not a permission or Outlook related issue, as we are able to send from the shared mailbox through Outlook and it correctly goes in to the shared mailbox sent items folder.
The issue occurs for all users that have to do this and does not matter what version of Outlook they have. Some have 2010, others 2013 and some 2016.
Any ideas if there is a setting that needs to be added on Sharepoint or to the template?