Hi @Plat, Noé,
Thank you for posting your question in the Microsoft Q&A forum.
I took some time to test the exact behavior you described in my own environment, and I can confirm that the New Outlook for Windows currently has this same limitation. Once a meeting invite has been declined, the desktop client does not provide a way to adjust the RSVP afterward, even if you restore the item to your inbox or reopen it. So you’re not missing anything; it’s simply a feature gap in the new Outlook experience compared to Outlook classic.
I’m also glad you shared in your update that you were able to change your RSVP using the mobile app. It’s not the perfect experience, of course, but it does give you a workable temporary solution so you can get things done in the meantime.
I know this isn’t the outcome you were hoping for, but as a forum moderator I’m not able to modify product behavior directly. Because of that, I strongly encourage you to submit your feedback to the New Outlook team through the official feedback portal: Outlook (new) · Community
This portal sends your idea directly to the product group, and user submissions like yours play an important role in shaping upcoming improvements. As you mentioned, this is the most effective way to ensure Microsoft doesn’t overlook such an essential feature. The ability to revise meeting responses after declining is absolutely a core workflow, so your feedback is genuinely valuable.
If you do post feedback, feel free to share the link here, I’ll be happy to vote for it to help give it more visibility.
Additionally, if you’re able to, please consider clicking “Accept Answer”. This helps surface your post at the top and highlights the current limitation so that other users who encounter the same behavior can easily find it and add their support to your feedback. Your voice genuinely matters, and collective feedback is a powerful way to help drive meaningful improvements.
Thank you for your understanding!
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