Configuration options for EWS in Exchange

Find information about configuration settings that your EWS client can access, and the configurable Exchange settings that can affect your EWS client.

Last modified: March 09, 2015

Applies to: EWS Managed API | Exchange Online | Exchange Server 2013 | Office 365

In this article
Configuration settings that clients can access
Configuration settings that administrators can access on the Exchange server
Additional resources

Many configuration settings can affect what your EWS client application can do. These configuration settings are either:

  • Read-only or read-writeable from the client.

  • Accessed on the Exchange server that hosts your EWS service.

A client can access settings on Exchange Online, Exchange Online as part of Office 365, and an on-premise Exchange server. All on-premise Exchange server settings are available to Exchange administrators; however, not all of these settings are available to Exchange Online tenant administrators. This article describes which configuration settings clients, Exchange Server administrators, and Exchange Online tenant administrators can access.

Your client application can get and set a number of configuration options from the Exchange server. Configuration settings that all EWS applications need are provided by the Autodiscover service. Other configuration settings are used for specific application scenarios.

Table 1. Web service features that provide configuration options for EWS clients



Autodiscover service

The Autodiscover service provides your client applications with configuration information so that your client can automatically configure itself to communicate with EWS.

Custom configuration information stored in a mailbox

You can use one of several options to store custom configuration information in your mailbox: user configuration objects, custom items, or extended properties.

Delegate management

EWS provides CRUD operations for managing delegate access to a mailbox. Delegates are users who have been given permission to access another user’s mailbox.

You can use the delegate management operations to enable delegate management by using EWS, or, if you’re using the EWS Managed API, you can use the following methods:

eDiscovery search configuration

eDiscovery client applications can get search configuration information that includes an eDiscovery search query, a list of searchable mailboxes, and the identifier of in-place mailbox holds.

Folder permissions

Folder permissions limit what a user can do in a public folder, and in the case of delegate access, what a delegate can do in another user’s folder. You can use either the Folder.Bind method or the GetFolder operation to access the permission set of every folder, including public folders, shared private folders, or folders to which users have delegate access.

Mail tips, Unified Messaging, or protection rules

The GetServiceConfiguration operation provides read-only service configuration information for mail tips, Unified Messaging, and protection rules.

Most client application scenarios don’t require changes to server configuration settings; however, some scenarios do. For example, to enable a middle-tier application to act as a user, you need to set Exchange Impersonation on the server. Note that some settings can only be accessed on on-premise Exchange servers. If you are targeting Exchange Online, your client application might need to work with the default settings.

Table 2. Exchange server configuration options that affect EWS clients


Accessible from Exchange Online?

For more information, see…

Virtual directory settings (including authentication)












Retention hold

Data loss prevention

Delegate management


Manage Permissions for Recipients

Exchange Impersonation


Configure Exchange Impersonation

Mail tips, Unified Messaging, or protection rules



Unified Messaging Cmdlets

Outlook Protection Rules



Throttling settings

User agent filtering


User agent filtering