Prism Email Router

Keep Dynamics 365 on-premise in sync with Exchange Online using Microsoft Graph - no EWS, no migration to the cloud.

Microsoft is retiring server-side sync for Dynamics 365 on-premise

Exchange Web Services (EWS) is being removed from Microsoft Exchange Online in October 2026. That means the built-in server-side synchronisation between Dynamics 365 on-premise and Exchange will no longer work. Microsoft’s guidance is to migrate to Dynamics 365 Online - but if you need to stay on-premise, Prism Email Router is the solution!


Why choose Prism Email Router?


Uses Microsoft Graph API

We use the supported, modern way to access Exchange Online. No dependency on EWS, so you’re ready for the future.

No changes to Dynamics

Your Dynamics 365 environment stays as it is. No schema changes, no customisations—just configure the router and go.

Simple to configure

Create an application with the right Graph API permissions in the Entra admin console, add a user account for Dynamics access, and you’re set.

Installed on your infrastructure

The application runs on your own infrastructure. No 3rd party access to your mailboxes or Dynamics is required. You stay in control.

What you get

  • Support for user mailboxes and queues
  • Continue using the Dynamics App for Outlook
  • Full on-premise solution