I have used Thunderbird for many years and for a long time have used Imap for my inbox. Recently my ISP's email server crashed and I have had problems since then with synchronisation. My Windows XP machine spends its whole time synchronising and often says that it is downloading, for instance, No 345 of 209 which makes no sense. Later on it will say that it is downloading a lower number and then it carries on until once again it is downloading a higher number than is in the folder. It never seems to finish synchronisation. Many thanks Rob Dixon