I have found Chrome works well, really quick and easy to use. As I said earlier Thunderbird has stopped asking for my Password, so I can put up with the SLOW start. THANKS for the help. I consider my problem to be solved.
I installed Raring today from the latest ISO, and Thunderbird worked just fine. When I opened it to set up my account, it found it and logged me in just as it should. So I don't know if the problem was with Thunderbird or with something else, but it's all good now.
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