Sending, receiving, and organizing email in Outlook.com
In web Outlook, turn the Reading Pane away from the inline preview mode that is causing the message to open while selecting mail.
Use either of these supported layouts:
- Go to Settings > Mail > Layout.
- Under Reading pane, choose:
- Right or Bottom if mail should open in the same screen, or
- Popout only if a reading pane should not display.
- Save the change, then refresh the page if needed.
If the problem is that messages are being marked read while selected, the reading pane settings also include read behavior controls. In Outlook mail settings, under Reading pane, these options are available:
- Mark the item displayed in the reading pane as read
- Mark the item as read when the selection changes
- Don’t automatically mark items as read
If the goal is to stop mail from opening in a separate browser side pane in Microsoft Edge, turn that off in Edge:
- Open the Edge sidebar settings.
- Under App and notification settings, select Outlook.
- Turn off Automatically open Outlook email context in the side pane.
- Mail settings
- Use and configure the Reading Pane to preview messages in Outlook
- Web links from Outlook emails and Teams chats open in Microsoft Edge
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