In Cached Exchange Mode, Outlook 2016, Outlook 2019 and Outlook for Office 365 still query WDS desktop search indexes. Search in Outlook 2016 and later versions Why am I still talking about WDS? Because it is still relevant, even when using the latest and greatest versions of Outlook and Exchange. WDS does not index the mailbox store directly. It is this local file that is indexed by WDS. When an Exchange email account is in Cached Exchange Mode, the mailbox contents are synchronized to the local. Let us focus strictly on searching Exchange mailbox content. Exchange content is indexed by WDS when Outlook is configured to connect to the Exchange mailbox using Cached Exchange Mode. The use of WDS in Outlook is sometimes referred to as Instant Search. At the same time, Outlook uses the same WDS architecture to search these local indexes when you initiate a search. These indexes are created on the local disk. For more information about the migration of Exchange Online search features to Microsoft Search, see How Outlook for Windows connected to Exchange Online utilizes Microsoft Search.Īs far back as in Outlook 2007, Outlook has utilized Windows Desktop Search (WDS) to index Outlook Data (.pst) and Offline Outlook Data (.ost) files.

However, on-premises Exchange Server will continue to use FAST search. * Note Exchange Online on Microsoft 365 is migrating search features from FAST to Microsoft Search.

The new feature set is readily available when using Outlook on the Web to connect to a mailbox on Exchange Server 2016 or Exchange Online.* Additionally, the newer Outlook 2016 desktop client also takes advantage of the new FAST search when connecting to these same mailboxes. These suggestions are dynamically computed based on your previous searches and the names of people that you frequently communicate with. With FAST search, various new features are made available to Exchange 2016 mailbox users, including Search suggestions and People suggestions. With Microsoft Exchange Server 2016, the FAST search architecture is introduced to Exchange. The term FAST Search may not be entirely new to you if you managed SharePoint sites anytime during the last decade.

Why cached exchange mode outlook 2016