Hi @Jones, Cameron
Thank you for posting your question in the Microsoft Q&A forum.
I'm sorry to hear your coworker is experiencing this issue. It sounds like you've been very thorough with troubleshooting, which can be frustrating when nothing seems to work.
To clarify this issue, please provide your Outlook version and product details. You can find this information by going to Outlook > File > Office Account. What version of Outlook do I have? - Microsoft Support
Based on my research, here are some suggestions that you may try:
-First, try restarting your Outlook and Windows system to see if that resolves the issue.
Start > Settings > Update & Security > Troubleshoot.
Find and click on Search and Indexing > Run the troubleshooter to help diagnose the issue.
-Verify indexing status:
Open Outlook > Search box > Search Tools > Indexing Status
you should see the number of items remaining to be indexed
If Outlook has not finished indexing, note the number of items remaining, wait 5 minutes, and check again. If the number of items has not decreased, proceed to the next step.
-Follow the instructions in this article to Rebuild the Outlook Search Index Fix search issues by rebuilding your Instant Search catalog - Microsoft Support
-If these steps don't resolve the issue, consider creating a new Outlook profile. Sometimes, a corrupted profile can cause search problems.
For more information, you may take this article as a reference Troubleshooting Outlook search issues - Microsoft Support
If the license was provisioned through a third-party vendor, sometimes missing or misconfigured Exchange Online licenses can cause search functionality to break.
If you haven’t already, I recommend verifying the following:
-Ensure the user has an active license that includes Exchange Online.
-Check for any group-based licensing errors in the Microsoft 365 Admin Center.
You need to be a Global Admin to verify and check licensing. If you don't have these permissions, you might need to reach out to an IT administrator in your organization.
I hope this helps! If you have any other questions, feel free to ask.
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