Mentions not working in outlook. No setting to enable the mention option

Hi Yogesh Punde, 

Thank you for posting your question in the Microsoft Q&A forum. 

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I understand how frustrating it can be when a feature seems to be missing from the settings. I appreciate your patience while looking into this. I’ve done some research and testing in my own environment to better understand the issue you're facing, and I’d like to share a few insights that may help clarify things. 

I tested using the same account across two different Outlook versions: 

• Microsoft 365 Apps for enterprise 
• Microsoft Office Professional Plus 2016 

Based on the results, it appears that the @mention feature in send message settings is only available in Outlook as part of Microsoft 365 Apps. Unfortunately, Outlook 2016 does not support this feature, and there’s no way to enable it within that version, this seems to be a design limitation. 

As a possible workaround, you might consider asking your IT administrator if it’s feasible to switch your Outlook client to the Microsoft 365 version of Classic Outlook, which does support the mention feature. 

I hope this information provides some clarity on the current limitations. If you have any further questions, feel free to reply here! 

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