Outlook Search Not Working? How to Get Results Back

You type a sender's name or a keyword into Outlook, hit Enter, and get nothing back, or only a handful of messages when you know there are dozens. Maybe recent emails are missing, or you see "No matches found" on a mailbox you search every day.

Most of the time this is fixable in a few minutes, and the fastest fixes have nothing to do with anything broken. The trick is knowing which Outlook you are using, because they behave completely differently. Classic Outlook for Windows leans on the local Windows Search index, so indexing fixes apply. New Outlook for Windows, Microsoft 365, and connected Exchange accounts use server-side "Service Search," so the index-rebuild steps will not help them.

Work through the checks below in order. The quick scope and filter checks come first because they resolve the largest share of "search not working" reports, then we move into indexing, services, and deeper repairs.

Check Your Search Scope, Filters, and Online Status First

Before assuming anything is broken, rule out the settings that silently hide results. These take under a minute and apply to classic Outlook for Windows.

Click in the Search box, then on the ribbon open the scope dropdown next to it. Options run from Current Folder to Subfolders, Current Mailbox, and All Mailboxes. If you expect a message from another folder, widen the scope.

1. 1.Click in the Search box, then select Search Tools > Indexing Status. If items are still being indexed, note the count, wait about five minutes, and re-check.
2. 2.Select Search Tools > Locations to Search and confirm every data file or store you want included is ticked.
3. 3.Clear any active filter chips shown below the search box; a leftover date or category filter restricts results.
4. 4.Look at the bottom-right status bar. If it reads Working Offline, turn it off via Send/Receive > Work Offline so server-side results are fetched.

In new Outlook for Windows, scope lives under Settings > General > Search. Note that multi-account search is not supported there; select each account individually and search All Folders.

Show All Results by Removing the Result Cap

If search returns results but stops short, classic Outlook is probably limiting them. By default it shows 250 results.

Go to File > Options > Search and clear "Improve search speed by limiting the number of results shown." Click OK, then restart Outlook. Your full result set should now appear.

Include Deleted Items and Cache More Mail

Two settings decide whether older or deleted messages are even available to search. If the message you want lives in Deleted Items, or is older than what Outlook keeps on the device, search will never find it.

In classic Outlook, to include deleted messages, open File > Options > Search, enable "Include messages from the Deleted items folder in each data file when searching in All Items," click OK, and restart Outlook.

To keep more mail locally so older messages are searchable, go to File > Account Settings > Account Settings, select the Email tab, select the account, click Change, then drag "Download email for the past:" to a longer period or All. Click Next, then Done, and restart Outlook.

In new Outlook for Windows, the equivalents are Settings > General > Search ("Include deleted items," then Save) and Settings > General > Offline (open the "Days of email to save" dropdown, choose a longer timeframe, then Save). Online Archives are searched and included automatically there.

Confirm Indexing Has Finished

In classic Outlook, partial or empty results often just mean Windows is still building the index. This is normal after a Windows 11 upgrade, which deletes the index and rebuilds it afterward, so your locally stored PST or OST data is temporarily unsearchable.

Click the Search box, select Search Tools > Indexing Status, and wait for indexing to complete. Microsoft warns a full rebuild "might take a long time to complete," and in some cases it runs for several days. Results stay incomplete until it finishes.

Run the Windows Search Indexer Troubleshooter

If indexing seems stuck, let Windows diagnose it. Use the path for your OS.

• Windows 11: Start > Settings > Privacy & Security > Troubleshoot > Searching Windows > Indexer troubleshooter.
• Windows 10: Start > Settings > Update & Security > Troubleshoot > Search and Indexing > Run the troubleshooter.
• Windows 8.1: Start > Settings > troubleshooting > Search and Indexing troubleshooter.
• Windows 7: Control Panel > Troubleshooting > Search and Indexing troubleshooter.

Verify the Windows Search Service Is Running

Classic Outlook depends on the Windows Search service for POP, IMAP, and offline-Exchange accounts. If it is stopped or set to the wrong startup type, search breaks.

1. 1.From the Start menu, type services.msc and press Enter.
2. 2.Find Windows Search in the Name column and double-click it.
3. 3.Set Startup type to "Automatic (Delayed Start)."
4. 4.If Service status is not Running, click Start.
5. 5.Click OK and restart Outlook.

Make Sure Outlook Is Included in Windows Indexing

If the Outlook data file was never added to the indexed locations, or the message-content filter is missing, contents are not indexed.

1. 1.Exit Outlook.
2. 2.Open Control Panel > Indexing Options (or type "Indexing" and choose Indexing Options).
3. 3.Confirm Microsoft Outlook appears under Included Locations. If missing, click Modify, tick the box next to Microsoft Outlook, then OK and Close.
4. 4.Click Advanced, select the File Types tab, scroll to the "msg" extension, and select it.
5. 5.Confirm "Index Properties and File Contents" is enabled and that the Filter Description shows "Office Outlook MSG IFilter."
6. 6.Click OK, then Close.

Rebuild the Instant Search Catalog

When indexing is corrupted, a rebuild often clears it. This applies to classic Outlook (Microsoft 365 and Outlook 2024, 2021, 2019, 2016).

1. 1.Close Outlook completely.
2. 2.Open Control Panel > Indexing Options.
3. 3.Confirm Microsoft Outlook is an included location under "Index these locations."
4. 4.Click Advanced to open Advanced Options.
5. 5.On the Index Settings tab, under Troubleshooting, click Rebuild.
6. 6.Click OK on the warning to start the rebuild; it runs in the background.

You can also reach this from inside Outlook via File > Options > Search > Indexing Options > Advanced > Rebuild. Allow plenty of time, as it may take several days.

Fix "0 Items Indexed" or "No Matches Found"

If Indexing Status shows "0 items indexed," or a remaining count that never decreases, suspect the "Allow service to interact with desktop" setting on the Windows Search service (this triggers Event ID 3100, error 0x800705b4).

1. 1.Exit Outlook (and Microsoft Lync or Communicator if running).
2. 2.Run services.msc.
3. 3.Right-click the Windows Search service and select Properties.
4. 4.Click Stop and wait for it to stop.
5. 5.Select the Log On tab and clear the "Allow service to interact with desktop" checkbox.
6. 6.Click Apply, select the General tab, click Start, wait, then click OK.
7. 7.Start Outlook.

Install the Windows Update for the Indexing Regression

A known Windows update (KB5008212) and the Windows 11 upgrade caused the Windows Search service to index slowly or pause, so recent emails went missing for POP, IMAP, and offline-Exchange accounts. Microsoft 365 and connected Exchange accounts use Service Search and are unaffected.

Install the permanent fix for your OS: Windows 10 KB5011543, Windows 11 KB5011563, Windows Server 2019 KB5011551, or Windows Server 2022 KB5011558. The Windows 11 indexer-speed fix is KB5015882 (OS Build 22000.832). If results are still missing afterward, rebuild the index via File > Options > Search > Indexing Options > Advanced > Rebuild and allow time to finish.

Force Outlook's Built-In Search as a Temporary Workaround

While the index rebuilds on a POP, IMAP, or offline-Exchange account, you can switch classic Outlook to its own built-in search by disabling Windows indexing of Outlook. Back up the registry first; Microsoft warns that serious problems can occur if you modify it incorrectly.

1. 1.Press Windows + R, type regedit, click OK.
2. 2.Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows.
3. 3.Right-click the Windows folder > New > Key and name it "Windows Search."
4. 4.Select the new key, right-click the right pane > New > DWORD Value, and name it "PreventIndexingOutlook."
5. 5.Double-click it, set the value to 1 (set 0 to undo), click OK.
6. 6.Close the editor and restart Outlook.

Outlook will then show "Search performance will be impacted because a group policy has turned off the Windows Search service." That message is expected here, not a new error.

Search Shared Mailboxes and Online Archives Correctly

Searching a shared mailbox or online archive with All Mailboxes or All Outlook Items is a documented design limitation that returns incomplete results and will not change in future updates. Auto-expanding archive storage adds another catch: each subfolder must be searched separately.

The simplest fix is to select that mailbox or folder and switch the scope to Current Folder. If you need broader behavior, choose only one of these workarounds:

• Disable server-assisted search via the registry: HKEY_CURRENT_USER\software\policies\Microsoft\office\16.0\outlook\search, create DWORD DisableServerAssistedSearch = 1 (an alternate key is HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Search), then restart.
• Add the shared mailbox as its own account: File > Account Settings > Account Settings, double-click the Exchange account, More Settings > Advanced, remove the shared mailbox under "Open these additional mailboxes," then File > Add Account, enter the full shared address, and sign in with credentials that have permission.
• As a last resort that degrades performance: File > Account Settings > Account Settings > select account > Change > More Settings > Advanced > uncheck "Download Shared Folders."

Work Around the Non-English Filter Bug

In some non-English builds, picking a Suggested Search or using the built-in Received filter generated an invalid query operator and returned "No results." To work around it, manually correct the operator or date format, or type the English query equivalent. The permanent fix shipped in the updates (Received filter in build 16125.10000; Suggested Searches on April 17, 2023), so update Office and then revert any DisableServerAssistedSearch registry change you set for this.

Repair Office or Test a New Profile

If search still fails, a broken Office install or a corrupt profile may be the cause. To repair Office, right-click Start > Apps and Features (Installed apps on Windows 11), select your Office product, click Modify, and choose Quick Repair first, then Online Repair if needed. Reopen Outlook and let it reindex.

To isolate a corrupt profile, exit Outlook and open Mail in Control Panel, click Show Profiles > Add, name the profile and finish setup, select "Prompt for a profile to be used," then restart Outlook, choose the new profile, and test search.

Fix Search in Outlook for Mac

On Mac, search problems usually trace to incomplete or corrupted Spotlight indexing. If you just created a profile, added an account, or imported data, wait for indexing to finish; a "No Results" message until then is normal.

Check the profile name for special characters such as "/", since that breaks indexing. The profile lives at /Users/<user>/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/ (default "Main Profile"). To reindex, restart the Mac, open Terminal, and run mdimport -L. If more than one "Microsoft Outlook Spotlight Importer.mdimporter" appears, you have two Outlook apps installed; delete the unused one, empty Trash, restart, and start over. Then reindex with mdimport -g pointed at the importer and your profile path. If it still fails, uninstall and reinstall Office for Mac.

Fix Search in Outlook for iOS and Android

On mobile, start simple. Force close the Outlook app and reopen it; that resolves most incomplete or incorrect data. If results are still wrong, open the app, go to Settings, select the email account, and tap Reset Account. If the app crashes on open, clear the device browser cache, then remove and reinstall the app, or remove and re-add the account.

Frequently Asked Questions

Why does the index rebuild take so long? Microsoft states a rebuild "might take a long time to complete," and on large mailboxes it can run for several days. Search results stay incomplete until indexing finishes, so check Indexing Status before assuming it is still broken.

I rebuilt the index but my Microsoft 365 search is still wrong. Why? Microsoft 365 and connected Exchange accounts use server-side Service Search, not the local Windows index. Index rebuilds, the KB updates, and the PreventIndexingOutlook key only help POP, IMAP, and offline-Exchange accounts.

Why can't I search all my accounts at once in new Outlook for Windows? Multi-account search is not currently supported in new Outlook for Windows. Select each account individually and search in All Folders.

Search returns only 250 messages. Is that a bug? No. Classic Outlook caps results at 250 by default. Clear "Improve search speed by limiting the number of results shown" under File > Options > Search to see everything.

My colleagues and I all suddenly got a "trouble fetching results from the server" error in cached mode. Can I fix it? If this began after the March 2024 Exchange Server security update, it is a server-side regression; online mode and the web version are not affected. End users cannot fix it from the client. A server administrator must apply Microsoft's Exchange Server fix for this issue.

After fixing search, results still look wrong. What did I miss? Re-check the scope dropdown (All Mailboxes, Current Mailbox, or Current Folder) after any repair or rebuild. A narrow scope is the most common reason search still appears broken once the underlying issue is fixed.