Fix Outlook Search Not Working - Rebuild Index & Reset Data

If your Outlook search is spinning forever or just returning empty results, your search index is likely corrupted or your local data file has drifted out of sync. I fix this daily on helpdesk tickets, and it usually comes down to forcing the application to rebuild its local search footprint.

Why this happens

Outlook relies on a local index for speed, but frequent updates or large mailbox shifts often cause this index to hang or corrupt. Renaming the local data file forces Outlook to discard the broken cache and rebuild a healthy connection to your server.

What you'll need

Make sure you have your account password handy, as you may need to sign back in after clearing your local data. You will also need to be able to close Outlook entirely via Task Manager.

Steps

1. 01
   Check for pending Windows updates by searching 'update' in your taskbar and installing any available patches.
2. 02
   Open 'Indexing Options' via your Windows search bar, click 'Advanced', then click 'Rebuild' to refresh your search database.
3. 03
   Press Ctrl + Shift + Esc to open Task Manager, find 'Outlook' in the list, and select 'End task' to ensure the app is fully closed.
4. 04
   Press Windows Key + R, type 'C:/Users/[YourUsername]/AppData/Local/Microsoft/Outlook', and press Enter.
5. 05
   Locate your 'Outlook data file' (ending in .ost), right-click it, and rename it to something like 'old_data.ost'.
6. 06
   Open Outlook again; it will automatically generate a fresh data file and begin re-syncing your mailbox.
7. 07
   Wait for the status bar at the bottom of Outlook to finish 'Updating' or 'Syncing' before testing your search again.