My Thunderbird does not seem to want to download messages from frontier.com today. It is using the same e-mail address and password that it has used for years without any problems (including through yesterday), and I have not changed them. It says that the host is contacted and it is sending login information, and nothing more happens. I can reach frontier.com directly by Mozilla (or Safari on my iPad), but Thunderbird seems to have gone dead. What can I do?