I previously posted an article https://community.bt.com/t5/Email/Re-POP3-no-longer-marks-emails-as-read-YAHOO-change/td-p/1982275. At first, I thought that the posted solution had cured the problem. However, it did not and, since then, the situation seems to have worsened. I use Outlook 2016, the email client is set to IMAP and I have adjusted the email settings to correspond to the solution posted on http://bt.custhelp.com/app/answers/detail/a_id/44917/kw/bt%20mail/c/6591.
Is anyone else having a problem whereby emails do not get marked as being 'Read' after having double clicked on an email or even when attempting to explicitly mark them as Read using Outlook's Unread/Read button?