Hi @Mary-Powel Thomas ,
Welcome to our forum!
Based on my test, i find that when I have enough Outlook windows open, they are displayed in portrait orientation, which reproduces your issue. Also, I do the same test on multiple browser windows and the results were the same. I'm afraid the issue is more related to Windows settings.
Please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. It's suggested that you could post your issue with "Windows Server" tag to get more professional suggestions.
Thanks for your understanding and support!
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