Outlook.com (the current name for Hotmail) no longer supports switching back to the old “legacy” interface. The modern Outlook.com layout is the only supported web experience, and there is no setting to fully revert to the historical Hotmail look.
However, some visual clutter can be reduced by customizing the mailbox appearance and layout in Outlook.com/Outlook on the web. For example, layout and reading pane options can be adjusted, and the look and feel of the mailbox can be personalized to be simpler. For detailed steps on changing the appearance and layout, see the Outlook.com mailbox personalization guidance in the referenced article.
If additional help is needed beyond what the built‑in settings allow, support options and community forums for Outlook.com are available, where questions can be posted and answered by support agents and other users.
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