check box to mark bulk emails

Click the Select icon—the small box at the right of the current folder’s name—to restore the checkboxes for bulk actions in Outlook.com.

1. Open Mail and select Inbox or another folder.
2. In the message-list pane, find the folder name above the messages.
3. Click the Select box icon on the folder name’s right side.
4. Checkboxes should appear to the left of each message.
5. Select the messages, then choose Delete or Move to from the command bar.

This control can hide the previously always-visible checkbox column until selection mode is activated; it is not an option under Settings.^1^ The same resolution applies to reports where checkboxes recently disappeared in both new Outlook and the browser.^2^

If using Outlook on a phone or tablet

The mobile interface does not use a permanently visible checkbox column:

1. Long-press a message or tap its circular sender icon.
2. Tap additional messages.
3. Tap Delete, Archive, or … for Move and Select All.^3^

References

1. Check boxes have disappeared - Microsoft Q&A
2. How to re-enable check boxes to select multiple emails for bulk actions? - Microsoft Q&A
3. How do I select multiple emails? | Microsoft Support