Added IP addresses whitelisting pre-requisite check

power-platform/admin/connect-exchange-server-on-premises.md

@@ -3,11 +3,11 @@ title: "Connect to Exchange Server (on-premises) | MicrosoftDocs"
 description: Connect to Exchange Server (on-premises)
 ms.component: pa-admin
 ms.topic: conceptual
-ms.date: 09/24/2021
+ms.date: 10/16/2023
 author: DanaMartens
 ms.subservice: admin
 ms.author: dmartens
-ms.reviewer: jimholtz
+ms.reviewer: sericks
 search.audienceType: 
   - admin
 ---
@@ -27,19 +27,20 @@ For more information about authentication, go to:
 
    - Exchange Server 2013: [Authentication and Exchange Web Services (EWS) in Exchange](/exchange/client-developer/exchange-web-services/authentication-and-ews-in-exchange)  
    - Exchange Server 2013: [Default settings for Exchange virtual directories](/exchange/default-settings-for-exchange-virtual-directories-exchange-2013-help) 
-   - Exchange Server 2016: [Default settings for Exchange virtual directories](/Exchange/clients/default-virtual-directory-settings?view=exchserver-2019)
-   - Exchange Server 2019: [Default settings for Exchange virtual directories](/Exchange/clients/default-virtual-directory-settings?view=exchserver-2019)
+   - Exchange Server 2016: [Default settings for Exchange virtual directories](/Exchange/clients/default-virtual-directory-settings?view=exchserver-2019&preserve-view=true)
+   - Exchange Server 2019: [Default settings for Exchange virtual directories](/Exchange/clients/default-virtual-directory-settings?view=exchserver-2019&preserve-view=true)
 
 3. **ApplicationImpersonation role**. You need to create and configure a service account with the **ApplicationImpersonation** role in [!INCLUDE[pn_Exchange](../includes/pn-exchange.md)]. [!INCLUDE[proc_more_information](../includes/proc-more-information.md)] [Impersonation and EWS in Exchange](https://msdn.microsoft.com/library/office/dn722377\(v=exchg.150\).aspx) 
 
 4. **Secured connection**. The connection between customer engagement apps and Exchange must be encrypted via [TLS/SSL](/windows/win32/secauthn/cipher-suites-in-schannel) and current [cipher suites](server-cipher-tls-requirements.md). 
 
-5. **Exchange Web Services (EWS)**. Connections to EWS must be allowed through the firewall. Often a reverse proxy is used for the exterior-facing connection.  
+5. **Exchange Web Services (EWS)**. Connections to EWS must be allowed through the firewall. Often a reverse proxy is used for the exterior-facing connection. If your EWS endpoint is not exterior-facing, review [IP addresses required](online-requirements.md#ip-addresses-required). Be sure to add IP addresses to the allow list on your on-premises firewall, based on your Dynamics 365 online environment region to allow connections to your Exchange server that is on-premises.
+
 
 > [!TIP]
 > To make sure you've got a good connection to [!INCLUDE[pn_Exchange](../includes/pn-exchange.md)] (on-premises), run the [Microsoft Remote Connectivity Analyzer](https://testconnectivity.microsoft.com/). For information about which tests to run, see [Test mail flow with the Remote Connectivity Analyzer](https://technet.microsoft.com/library/dn305950\(v=exchg.150\).aspx). 
 >
-> For ports required, see [Network ports for clients and mail flow in Exchange](/exchange/plan-and-deploy/deployment-ref/network-ports?view=exchserver-2019).
+> For ports required, see [Network ports for clients and mail flow in Exchange](/exchange/plan-and-deploy/deployment-ref/network-ports?view=exchserver-2019&preserve-view=true).
 > 
 > To learn more about the protocols and ciphers used to secure the connection between Dynamics 365 and external email services, see [Server cipher suites and TLS requirements](server-cipher-tls-requirements.md).