emails from mybtinternet.com domain sometimes do not go to the recipients. These my be other btinternet.com users, or users of Outlook. The problem appears to be the security certificate of my btinternet.com domain. I spoke to BT about this, and they blame my use of Outlook, i.e. Microsoft. I had contact with Microsoft via chat, and they blamed BT. I am a user, and understand some of my contacts have found the same problem. However, emails used to always get through. The disappearing emails only started about a year or so ago. How can this be resolved please, as neither company seems interested in helping?