With Dynamics 2015 using the Outlook plugin:

  • New, outgoing email will not be tracked automatically
  • Incoming email will be tracked automatically
  • Outgoing email in response to a tracked email will be tracked automatically

With Dynamics 365 using server-side synchronization with Dynamics 365 App for Outlook:

  • New, outgoing email will not tracked automatically
  • Incoming email will be tracked automatically
  • Outgoing email in response to a tracked email will not be tracked automatically

The last of these six points seems like a bug. When an email is received and tracked, if a response is sent that email it is no longer tracking automatically. It used to. I have read of all the Microsoft documentation and support links on server-side synchronisation, setting up Dynamics 365 App for Outlook and category tracking, so please so not suggest links to those articles.

Please could someone try and reproduce, and confirm whether they believe this is intended behaviour and if so, why it has changed (a loss of functionality).