If your Outlook search function is not finding any of your messages, you may need to rebuild the search index. To solve the Outlook contact search not working issue first, choose 'File' then 'Options' then 'Search.' In the 'Change the Outlook stores indexed by Windows Search,' click 'Indexing Options' Now, select 'Advanced.' Now, in the 'Troubleshooting' section, select 'Rebuild.' Then, select 'Close' when finished. Then, click 'OK' to close out of options. 

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