Supported email service configurations for server-side synchronization

Depending on your Dynamics 365 Customer Engagement (on-premises) installation, you may be deciding whether to use server-side synchronization or the Email Router/Outlook synchronization. This following table lists email systems that server-side synchronization for each type of installation supports. Later in this topic, you can read about the scenarios that server-side synchronization doesn't support.


  • The information here includes the POP3/SMTP systems supported by Microsoft. Although other POP3/SMTP systems might work with Customer Engagement (on-premises), those systems were not tested by Microsoft and are not supported.
  • Outlook on the web is not supported in a hybrid deployment: Customer Engagement (on-premises) with Exchange Online.
  • You can create two different email server profiles: one for online mailboxes, and another for on-premises mailboxes. Associate the mailboxes with the correct email server profile.
  • Manual tracking in Dynamics 365 for Outlook is not supported when a user’s mailbox is configured to use server-side synchronization with the POP/SMTP protocol.
Dynamics 365 for Customer Engagement apps deployment Email system Email synchronization Appointments, contacts, and tasks synchronization Protocol
Customer Engagement (on-premises) - Exchange Online
- Exchange Server 2010
- Exchange Server 2013
- Exchange Server 2016
- Exchange Server 2019
Yes Yes Exchange Web Services
Customer Engagement (on-premises) - Gmail
- Yahoo! Mail
- MSN1
- Outlook.com1
- Windows Live Mail1

1 May be unsupported for FIPS-compliancy. See the following section for more information.

Unsupported email service configurations

Server-side synchronization doesn’t support the following scenarios:

  • Mix of Exchange/SMTP and POP3/Exchange

  • Exchange Online profile mailbox with Exchange on-premises user. Use the Exchange Server (Hybrid) profile, associate the mailbox to it, then test and enable.

  • Exchange Online profile mailbox with an Exchange mailbox that points to an external email server. Use the POP3/SMTP Server profile, associate the mailbox to it, then test and enable.

  • Creation of mass email marketing campaigns

  • Extensibility scenarios like extending EWS/POP3/SMTP protocols and creating custom email providers

  • Exchange Server 2003 and Exchange Server 2007

  • Server-side synchronization in Customer Engagement (on-premises) deployment that is configured for FIPS 140-2 compliancy, requires a POP3/SMTP email server that is also FIPS 140-2 compliant. Some email servers are not FIPS 140-2 compliant, such as MSN,, or Windows Live Mail.

  • The Customer Engagement (on-premises) to Exchange Online scenario doesn't support multi-factor authentication.

For most situations not supported by server-side synchronization, you can use the Microsoft Dynamics CRM Email Router. More information: Integrate your email system


We recommend that you don’t use a mixed configuration of Outlook synchronization and server-side synchronization for appointments, contacts, and tasks in the same organization, because it may result in updated Customer Engagement apps data not synchronizing to all attendees.

See also

Server-side synchronization
Set up server-side synchronization of email, appointments, contacts, and tasks