Announcing Exchange ActiveSync version 16.1

We are excited to announce enhancements to Exchange ActiveSync (EAS) in Office 365 and a future cumulative update to Exchange Server 2016 that will soon be available to Exchange ActiveSync clients.

We are introducing version 16.1 of the EAS protocol, which contains three new major capabilities:

  1. Improved Keyword Search - Get quicker, more relevant results when searching your inbox. Clients can now perform Keyword Query Language searches (from, to, subject, etc.) by using the new Find command.
  2. Propose New Time - Users have asked for the ability to propose a new time for a meeting while on the go, and we have added full support for new time proposals in EAS 16.1.
  3. Account-Only Remote Wipe - Administrators can now request clients using EAS 16.1 to wipe only Exchange data from a user's device.

While not a part of EAS 16.1, we also want to note that both Office 365 and customers can now utilize the OAuth 2.0 protocol for authorization through EAS.

Customers with their mailbox in Office 365 can take advantage of these new features when their favorite EAS client is updated.

Update: We are happy to share that iOS 10, announced June 13th at Appleā€™s Worldwide Developer Conference, plans to support the above features of EAS 16.1 when it releases in the fall. Apple has also announced support in the same release for draft email syncing, which was introduced in EAS 16.0, the OAuth 2.0 protocol for authorization of accounts and support for forwarding meeting items.

As an end user, how can you tell if your mailbox is enabled for EAS version 16.1? The simplest way is to run an "Exchange ActiveSync" test at and look for version 16.1 listed as one of the supported protocol versions (MS-ASProtocolVersions header in the OPTIONS command response) in the test results. Note that you need a valid Office 365 email address and password in order to run that test, and the results are specific to that mailbox only (not the entire tenant).

For partners who are building Exchange ActiveSync applications, preview documentation for EAS v16.1 is now available at