Classic Outlook issues with service assisted search for shared mailboxes

Last Updated: September 29, 2026

ISSUE

Server Assisted Search against Online Mailboxes does not update as results change.

Repro Steps:

This issue can be reproduced with a single mailbox in online mode.

1. Mailbox in online mode.

2. Pick a folder, do search for items within folder, "Current Folder" is scope.

3. Pick one of the search results and drag it to an adjacent folder.

   Expected result: Item vanishes from search
   Actual result: Item is still in search, we get errors trying to click on it.

   Note

   This issue may also occur for setting a category or marking an item as read / unread.

STATUS: FIX IN PROGRESS

This issue has been escalated as a hotfix to the Outlook Team, and a fix is in progress. There is no ETA yet. We will update this topic when the fix is available.

WORKAROUND

Temporarily disable Server Assisted Search, which will fall back to the legacy Windows Desktop Search, with the following registry key:

HKEY_CURRENT_USER\software\policies\Microsoft\office\16.0\outlook\search
DWORD: DisableServerAssistedSearch
Value: 1

Additional Resources

Troubleshooting Outlook search issues

How Outlook for Windows connected to Exchange Online utilizes Microsoft Search

Overview of Microsoft Search

More Resources

Ask the experts

Connect with experts, discuss the latest Outlook news and best practices, and read our blog.

Outlook Tech Community

Get help in the community

Ask a question and find solutions from Support Agents, MVPs, Engineers, and Outlook users.

Outlook Forum on Answers

Suggest a new feature

We love reading your suggestions and feedback! Share your thoughts. We're listening.

Find out how

See Also

Fixes or workarounds for recent issues in classic Outlook for Windows