Add checkbox in your outlook(2010/2013) emails.?? To do this: Open the View Tab. Click on view settings. Click New Column button. Create a custom field of the Yes/No type and add it to the view. Move it on the top. Click Other Settings. Enable in-cell editing so you can check (or uncheck) it to mark an item. Return to Outlook. Click in the column you just added to mark a message Note: The actual checkbox may not be visible in the column until you click it.