Clean up unwanted email messages in New Outlook (replacing old Mail app): Either view unwanted messages by sorting them alphabetically using the ‘From’ field, or searching for for an email address in the Search box. To sort, click on the filter icon at the top of the main pane and select Sort ❯ From (and then once, you have deleted emails return it to Sort ❯ Date). To select lots of emails to delete from say Amazon. Click on the first, hold down the Shift key then Arrow key down to select a block to delete. To search, type the email address into the search box and delete from there