Outlook Search Not Working? How to Fix It

You know the email exists. You can even see it in your inbox. But Outlook search returns "We couldn't find what you were looking for" or "No results", finds only recent messages, or shows "Search results may be incomplete because items are still being indexed". Sometimes search is greyed out altogether.

For anyone who lives in their inbox, broken search is a productivity killer. In classic Outlook, it's almost always a problem with Windows' search index or Outlook's cached mode settings. Here's how to fix it.

Why This Happens

Classic Outlook searches a local index built by Windows Search, not your mailbox directly. If that index is incomplete, corrupted or turned off, search fails. Other common causes:

• Search scope set to the current folder only.
• Cached Exchange Mode keeping only the last few months of email on your PC, so older messages aren't in the local index.
• Indexing still in progress after a new profile, a new PC or a large mailbox import.
• The Windows Search service disabled or stuck.
• Policies that prevent Outlook from being indexed.

Fix 1: Check the Search Scope

Click in the search box at the top of Outlook. A dropdown appears next to it showing the scope, such as Current Folder, Current Mailbox or All Mailboxes. Choose All Mailboxes or Current Mailbox and search again. You can set a default under File > Options > Search.

Fix 2: Check the Indexing Status

Click in the search box, then on the Search tab look for Search Tools > Indexing Status. If it says there are items remaining to be indexed, Outlook is still working. Leave the PC on and Outlook open, ideally overnight, and check again. A large mailbox can take hours.

Fix 3: Check Windows Search Is Running

1. Press Windows + R, type services.msc and press Enter.
2. Find Windows Search. Its status should be Running and startup type Automatic (Delayed Start) or Automatic.
3. If it isn't, right-click it, choose Properties, set the startup type and click Start.

If you can't change it, your organisation may have disabled it, so speak to your IT team.

Fix 4: Make Sure Outlook Is Being Indexed

1. In Outlook, go to File > Options > Search and click Indexing Options. (You can also find Indexing Options from the Start menu.)
2. Click Modify and make sure Microsoft Outlook is ticked.
3. Click OK.

Fix 5: Rebuild the Search Index

1. Open Indexing Options as above.
2. Click Advanced, then on the Index Settings tab click Rebuild.
3. Click OK. Keep Outlook open and give it time to finish, ideally overnight.

Fix 6: Find Older Emails

By default, Cached Exchange Mode may only keep a set period of mail on your computer, such as the last year. Older emails are still in your mailbox, but not in the local index.

• At the end of search results, look for a link such as Click here to view more on the server or More, which searches your full mailbox online.
• To keep more locally, go to File > Account Settings > Account Settings, select your account, click Change and move the Download email for the past slider. Outlook needs a restart and will download more mail.
• Remember that emails in an Online Archive are searched separately. Select the archive or use the All Mailboxes scope.

Fix 7: Repair Office or Rebuild the Profile

If search still fails, run a Quick Repair of Microsoft 365 from Settings > Apps > Installed apps (choose Microsoft 365, then Modify). If that doesn't help, create a new Outlook profile from Control Panel > Mail (Microsoft Outlook) > Show Profiles. Outlook rebuilds the local copy and index from scratch.

What About the New Outlook?

The new Outlook for Windows and Outlook on the web search your mailbox in Microsoft 365 directly, so Windows indexing doesn't affect them. If search fails in the new Outlook, check whether it also fails in Outlook on the web. If both fail, it's an account or service issue for your admin. If you're struggling with classic Outlook search, the new Outlook can be a useful workaround.

For Your Microsoft 365 Admin

• Check Group Policy or Intune settings that affect Windows Search or Outlook indexing. A policy that prevents indexing of Microsoft Outlook will break classic Outlook search.
• Large mailboxes and shared mailboxes added to the profile increase indexing load. Consider an archive policy and online archives for very large mailboxes.
• For search problems in Outlook on the web, check Service health in the Microsoft 365 admin centre.

How to Stop It Happening Again

Search issues are more common on PCs with full or slow disks, enormous mailboxes and inconsistent Outlook settings. Managed devices with SSDs, a sensible cached mode window, retention and archive policies for large mailboxes, and regular Office updates keep search fast and reliable.

When to Call in Help

If search problems keep returning, or you rely on finding old emails for client or compliance reasons, our IT support team can fix it remotely, and our managed IT service sets up mailboxes, archives and devices properly. Get in touch.

Related Reading

• Outlook Disconnected or Trying to Connect? Fix It
• Shared Mailbox Not Showing in Outlook? How to Fix It
• Outlook Keeps Asking for Password? How to Fix It