THIS !
"Jeronimo Fuerte
Oct 19, 2026, 9:46 AM
Other Outlook.com users have reported the same behavior, which appears to be related to a recent change in the message list interface rather than the reading pane size. A setting is being introduced in Outlook.com under **Settings > Mail > Message list > Layout, where some users can choose between Sender images, Checkboxes, and Name only. Selecting Checkboxes keeps them visible for selecting multiple messages"
**You have to click "View" on the Menu bar to see the "View Settings" icon.
"Message List" is the top option on the menu that comes up.
Scroll down to "Layout".
2nd Option lets you select "Checkboxes".
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I did that and the checkboxes came back including the one to the left of the name of whatever folder you are in at the time - if that folder has any emails in it.
That one disappeared long ago and you had to actually select an email for it to appear. Now it's there (visible) all the time which will make getting rid of my "Junk" folder contents a bit easier.