Security News > 2022 > January > Microsoft: KB5008212 Windows security update breaks Outlook search

Microsoft has acknowledged an issue triggered by a Windows 10, version 21H2 security update released during the December 2021 Patch Tuesday that leads to search issues in Outlook for Microsoft 365.
"After you install update KB5008212, recent emails may not appear in search results," Microsoft explained in a recently published Office support document.
Unlike the new bug, those problems started showing up in June 2020 after users began installing the first Windows 11 preview builds, which would delete the Windows search index being deleted during the upgrade process.
Customers were advised at the time that they could fix Outlook search not returning any results by setting up a registry key to disable Windows Desktop Search and switch to Outlook's search engine.
After the built-in search kicks in, Outlook warns that performance is affected, saying that the "Search performance will be impacted because a group policy has turned off the Windows Search service."
Microsoft recommends the same approach as a workaround until a fix is available for the search issues caused by the Windows 10 KB5008212 security update.
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