I have been using Thunderbird for many years. My account has not changed. The point I want to make is my e-mail has been working fine for a long time. So the question is what changed? The only change was the most recent update from ThunderBird. I am no longer getting any messages downloaded from my e-mail server. This is the first update that offered the calendar. I activated it and now I get no e-mail messages. I also do not get any error messages.