If you want to deactivate only Prophet, here are the steps.
- In Outlook, click File > Options > Add-ins.
- Now that you are on the Add-ins window of the options menu. Click “Go” as underlined in the picture below.
- A window will appear. Uncheck “Avidian Prophet” and “Avidian Prophet Ribbon”, and then “Ok”.
- Prophet Should be disabled. If these steps don’t work, start Outlook in Safe Mode.