Sometimes Thunderbird seems to fail to connect to British Telecom mail servers. BT mail servers have had problem for years and years and normally you have to wait for them to sort out their mail. Ridiculous for such a large company! So normally you just have to ignore any messages given by Thunderbird and wait for the 'problem' to magically go away. However this message which occurs at very irregular intervals is cured simply by restarting Thunderbird. So not really a question but something that might be easily solvable. I have about a dozen different email addresses in Thunderbird. Some connect via Imap, this one by pop3. This is the only one which stops connecting