I use Thunderbird to collect business email from BT. Business email are addreses that end @btconnect.com. Suddenly one of my email addresses failed to authenticate. I rang BT to find out why. Apparently BT business email uses Exchange servers. I don't know why they do that, I would have thought some sort of Linux server would be better and more efficient. Microsoft have decided that Exchange will no longer support POP3 where passwords are sent in the clear. It's too vulnerable to hacking.
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