When performing an Outlook Search using Outlook 365 or Outlook 2016/2019 against an Exchange server 2016+ or Exchange Online, the results do not show a global filing indicator. Previously this was the case with older client versions.
Updates to Microsoft Outlook 365/2016/2019 by Microsoft have changed the Microsoft Search experience to use FAST Search instead of the prior Windows Desktop Search (WDS).
FAST Search Results are not able to display the same icons as used by WDS. That's why they don't display our Global Filing Indicator (GFI) in the search results column.
Microsoft uses different searches based on various criteria such as server latency or result set size to determine which search to use, so sometimes the user experience may vary.
Change your Search context to All Outlook Items. This forces Outlook to use WDS results and you will see the GFI within the results.
Permanently disable FAST Search results using the DisableServerAssistedSearch registry keys discussed in this Microsoft Support article.
With this enabled, WDS results appear at all times and you will see the GFI for any search.
Disable Server Assisted Search
Group Policy registry path:
OCT registry path:
Disables Outlook from requesting and using Search results from Exchange for cached and non-cached mailbox items. Instead, it will use search results from the Windows search service.
Set to 1 to enforce.