M365 Changelog: Known Issue: Outlook search does not return results after upgrade to Windows 11

MC313286 – After upgrading to Windows 11, Outlook searches may return no result. This issue could happen with any account where the emails and other items are stored locally in PST or OST files such as POP and IMAP accounts. For Exchange and Microsoft 365 hosted accounts, this issue could affect offline search for the data in the locally stored OST files. 

During the Windows upgrade, the search index is deleted and requires time to get rebuilt after the upgrade is complete. 

How you can assess the status of indexing:

If users are impacted by this issue, they can use the following steps to see how many emails are left to index:

To confirm the index rebuilding status, do the following:

  • In Outlook, select the Search box.
  • On the ribbon, select Search Tools, and then choose Indexing Status.

If the indexing is taking too long and users need to urgently search, they can set a registry key that will tell Outlook to use its built-in search using the steps listed in this article under the temporary workaround section: 

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