While deleting mail from inbox in Mail, a box popped up asking me to log into something called SSLPost. Not knowing what this means, I tried to close this box - it won't go! Also, my mailbox won't close as the red close button has lost its colour. I can only close it by pressing exit mail on the file drop-down menu. Worse - my mail inbox messages are increasing all the time - up to 1848 as I write. Has anyone else had this happen. It almost looks like a virus which won't allow me to close it down and increases the message total constantly. Please help. I'm too old to know what the **** goes on inside computers.
Many thanks for your response and sorry for the delay. I needed someone to read your reply who was better at computer-fixing than me. It has worked - and the problem has gone away. I am so grateful to you.