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You can choose the Reading Pane's location on the View tab in the Layout group: right, bottom, off
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Reading Pane not in use
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Reading Pane on the right
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When you browse through your messages while the Reading Pane is in use, you might want that the messages are not marked as read.
You can change the Reading Pane settings on the View tab in the Layout group bey selecting Options from the drop-down menu.
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If "Mark items as read when viewed in the Reading Pane" and e.g. "Wait 5 seconds before marking items as read" is selected, messages are marked as read if you stay 5 seconds or longer in the same message.
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