I have tried to set up an iCloud email address but when I am asked to choose an icloud.com address, whatever I type in, I get a message saying that the address is already in use, so I tried to send a test email to the iCloud address I wanted. However, I could only send it from one of my previously registered addresses. It came back to me, which I thought suggested I could use that address. Only trouble is, I can't get it to show in Mac Mail. What am I doing wrong? Can anyone enlighten me please?