Hi Adam Ellis,
Welcome to Microsoft Q&A Forum! Have a good day and I hope you're doing well!
I sincerely apologize for the inconvenience and frustration you’re experiencing. I completely understand that an unexpected interface change can be upsetting and disruptive to your workflow, especially when it happens without warning. Please know that I’m here to support you and help resolve this as quickly as possible.
Could you please share some screenshots of your Outlook interface after the change occurred? You’re welcome to blur or hide any sensitive information before sending them. Alternatively, you may send the screenshots via the private messages, which I sent to you earlier, if you prefer to better protect your personal information.
Based on my testing in a virtual environment, Outlook continues to retain its default interface. One possible explanation is that your device may currently be displaying New Outlook. Could you please check the following for me?
1. In the top‑right corner of the Outlook window, do you see a “New Outlook” toggle that is turned on?
2. If so, please try turning it off to revert back to the Classic Outlook interface. Outlook may prompt you to restart the application and confirm the switch back.
I truly hope the steps above can help clarify what may be happening. I understand how unexpected changes like this can be confusing and impact your daily work, so I really appreciate your patience. Once I receive your sceenshots, I’ll be able to look into this more closely and continue assisting you toward a complete resolution.
If I’ve misunderstood anything or missed any detail, please don’t hesitate to let me know. I’ll be happy to adjust and assist further. Thank you very much, and I look forward to hearing back from you soon.
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