Unable to Search IMAP Emails in New Outlook on macOS

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Dear @Arya Wang,

Welcome to Microsoft Q&A Forum! 

Based on your description, I understand that you had unexpected behavior with searching for emails within the New Outlook app in your MacBook (macOS Sonoma version 14.7.7). 

Therefore, I have tried my best to research in all available documents from Microsoft and other sources to support you, but there is no official confirmation for a permanent fix. 

However, I also found these methods that you can try to see if they can help you: 

1.You may consult in this article for several methods that may be related to your case: Troubleshoot search issues in Outlook for Mac - Microsoft Support 

Also, you can see this link for more insights: Outlook search not working on Mac – how to fix the issue 

Please note that our support is limited to providing guidance based on official Microsoft documentation. Any third-party resources or references shared are intended solely for informational or consultative purposes. Microsoft does not guarantee the accuracy, reliability, or continued availability of third-party content, and we recommend exercising discretion when referring to such materials. 

2.If the issue still persists after trying methods in those links and the mailing is important for your work, I suggest that you may consider switching back to Legacy Outlook to see if you can search your emails. Here are the steps: 

• Open Outlook on your Mac. 
• In the top menu bar, click Help. 
• Select Revert to Legacy Outlook from the dropdown menu. 
• Outlook will close and reopen in the classic interface. 

Please note that accounts added in New Outlook will not automatically transfer to Legacy Outlook. You may need to re-add them manually. 

Reference: Outlook for Mac - Microsoft Support 

Also, I found a case that was partially similar to your case, you can take a look as well: Search not working on Outlook 16.79 on Mac Sonoma - Microsoft Q&A 

Besides that, I understand it's not comfortable that you may have to use Legacy Outlook. However, this issue seems like an unexpected behavior with the searching email of the New Outlook. Also, I found that many users discuss this issue in our forum as well. Therefore, the best course of action at this time is to submit feedback directly to Microsoft. You can do this by visiting the Microsoft Feedback Portal. Sharing your experience helps Microsoft prioritize feature improvements in this scenario. The more users report an issue, the higher the chance it gets addressed in future updates. 

And I appreciate that you have raised your voice in this issue. Your action can help others in our community who are facing the same concern. 

Once again, thank you for your time and understanding in this case. 

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