I have used Outlook for many years and like it. However, for reasons that I do not understand, the 'expand triangle', i.e. the little triangles to the left of the email that when clicked show the email conversation, went missing from the Inbox folder this morning. I see them in other folders and the emails associated with the conversations are still there. How do I fix this?


Weirdly, when I double click an email, the conversation appears.