I have a few BT email addresses and for some months now have had a problem receiving and sending emails with two of them using Thunderbird mailing system. As all of the addresses are set up the same it has been really frustrating trying to find out what has been causing this problem. Having spent a lot of time trying to find on line someone had suggested it could be caused by using CCleaner. I have uninstalled this program. I removed both email accounts from Thunderbird and the passwords and changed the passwords on BT Mail. I then added the 2 email addresses back onto Thunderbird and for the last few days I have not had a problem. I hope this will help other people having and perhaps BT could note this?