You can use SIP (phonecalls are via PC headset) or TAPI (phonecalls are via deskphone) on 3CX with Dynamics Telephony inbound and outbound dialer on Microsoft Dynamics 365.

For TAPI, follow these steps

1. Get the 3CX plugins from here
https://www.3cx.com/blog/releases/crm-plugins/

2. Run the setup and pick TAPI from the list of components to install

3. Restart the PC

4. Start Dynamics Telephony and launch Settings from the menu
– Pick TAPI from the Telephony Provider list
– In Provider Account set TAPI Version to 2.1

You should now be controlling your desktop phone

Troubleshooting:
– Try running Dialer from Start Menu > Run
– Select menu “Connect Using” and make sure 3CX driver in list
– If you have more than one address controlled by TAPI, you will need to specify it in:
Dynamics Telephony Cog > Settings > Provider Account > DN