Who is the mail provider? Strange as it may sound the answer is often dependent on the provider. For instance ATT customers must use a mailkey from their web site instead of a password.

My provider is Bell Aliant. I talked with them and they suggested changing my password - which I did. But it still only allows me to pick up my mail from Webmail.bellaliant. I've used Thunderbird for many years and never had this happen before. I've been getting lots of updates from Thunderbird and I wonder if something changed because of the updates. I hope this info is of some help. Many thanks

Happy Day! Thunderbird is now downloading my emails again! The only thing I did is in ACCOUNT SETTINGS - SERVER SETTINGS where it listed my 'user name' I replaced it with my full email address. And it works!! I had never changed my 'user name' so don't know what caused the problem, but this was a fix!

my guess is your provider changed the rules. Unfortunately most help desk staff are employed based on their ability to follow the script, not on knowledge, so changes of that kind unless the script is updated don't get to the support line.

I expect you are right, Matt. I'm going to try to get in touch with Bell Aliant help and suggest they update their scripts so that all of their employees are singing from the same songbook. Many thanks for your input.