Outlook Search Not Working — How to Fix It

Outlook’s search failing to find emails is a common frustration — you type a sender’s name or a keyword and get no results, or only partial results, when you know the email is there. The fix is almost always a corrupted or incomplete search index. Here is how to repair it.

1. Try Basic Search Fixes First

Before reindexing, check the quick causes:

• Make sure you are searching in All Mailboxes or Current Folder — look at the scope selector that appears in the search bar when you click it. If it is set to Current Folder, try switching to All Mailboxes.
• Check that the email is not in a folder excluded from search. Outlook searches all folders by default, but some configurations exclude the Junk Email folder.
• Try clicking in the search box and pressing Enter to run the search fresh rather than waiting for instant results.

2. Repair the Outlook Search Index in Windows Settings

The Outlook search index is managed by Windows Search. If it is corrupted or incomplete, rebuilding it fixes most search problems.

1. Go to Settings → Privacy & security → Searching Windows
2. Scroll down and click Advanced indexing options
3. In the Indexing Options window, click Advanced
4. Under Troubleshooting, click Rebuild
5. Click OK to confirm — Windows rebuilds the index from scratch

Rebuilding the index can take 30 minutes to several hours depending on the size of your mailbox. Outlook search is unreliable while the rebuild is in progress. The index status is shown at the top of the Indexing Options window — wait until it says “Indexing complete”.

3. Check That Outlook is Being Indexed

Outlook must be included in the Windows Search index to return results:

1. Open Indexing Options (search for it in Start, or via Settings → Privacy & security → Searching Windows → Advanced indexing options)
2. Click Modify
3. Expand the list and ensure Microsoft Outlook is ticked
4. Click OK

If Microsoft Outlook was not ticked, enabling it and allowing the index to rebuild will fix the search.

4. Repair Search from Within Outlook

Outlook has its own search diagnostic that can fix index problems:

1. Go to File → Options → Search
2. Click Indexing Options — this opens the same Windows Indexing Options window
3. If the status shows a problem, rebuild as described above

Also in File → Options → Search:

• Under Sources, confirm Include results only from: is set to All folders
• Untick Improve search speed by limiting the number of results shown if it is ticked — this can cut results short

5. Re-add Your Outlook Data File to the Index

If rebuilding the index does not help, try removing and re-adding the Outlook data file:

1. Open Indexing Options → Advanced → File Types
2. Scroll down and confirm .ost and .pst files have Index Properties and File Contents selected
3. Click OK and rebuild

6. Search Not Working After Windows Update

Windows updates occasionally reset the search indexing service. If search stopped working immediately after an update:

1. Press Win + R, type services.msc and press Enter
2. Find Windows Search
3. Right-click → Restart
4. Double-click it and confirm the Startup type is set to Automatic (Delayed Start)

If the service was set to Disabled after an update, changing it back to Automatic and starting it will restore search.

7. Use Instant Search as a Workaround

While the index rebuilds, you can search using Outlook’s filter option instead of the main search bar:

1. Open the folder you want to search
2. Click the View tab → View Settings → Filter
3. Use the filter criteria to find emails by sender, subject, date, or keyword without relying on the index

This is slower but does not depend on the search index.

Related Guides

• Outlook Not Syncing Emails — How to Fix It
• How to Search Emails in Outlook Effectively
• How to Create a Rule in Outlook

Search Returns Old Results But Not Recent Emails

If Outlook search finds older emails but misses recent ones, the index has not yet caught up with new messages. This commonly happens after:

• A large batch of emails arriving at once (newsletters, mailing lists)
• Migrating to a new mailbox or adding a new account
• Returning from holiday and downloading a backlog of messages

In these cases, wait 10–15 minutes for the index to process the new messages. You can monitor progress in Indexing Options — the status bar shows how many items remain to be indexed. If the count is not decreasing, restart the Windows Search service as described above.

Shared Mailbox and Archive Search

Outlook does not index shared mailboxes by default — only your primary mailbox is indexed. Searching a shared mailbox requires Outlook to perform a server-side search, which is slower. If search in a shared mailbox returns no results, this is normal behaviour rather than a fault. Use the date filter or From/Subject filters to narrow results when searching shared mailboxes.

Online Archive mailboxes (In-Place Archive) also perform server-side searches. Make sure you have expanded the archive in the folder list before searching, and select All Mailboxes in the search scope to include it.