Try the Error Console, under Tools in the menu, or ctrl+shift+j.

Zenos said

Try the Error Console, under Tools in the menu, or ctrl+shift+j.

Thanks for that tip which was useful.

However, the error console does not appear to include the pop-up notifications I am seeing.

What are you seeing? perhaps we can guess the rest.

You could also check the activity manager, it is also on the tools menu. But neither is designed to capture error dialogs. The information they contain may be useful or even pertinent, but it will not the the text of the error dialog.

The message is something like "The IMAP server xxx does not s..." and I'm guessing the s is support, but the important information about what is not supported is missing. (Notification text corrected Aug 4.)

Are you able to send and receive new mail for that new imap mail account? If no, have you selected to use imap via the webmail account?

Perhaps the message is this: 'The IMAP server does not support the selected authentication' Please post the following info: In thunderbird Help > Troubleshooting Information click on 'copy text to clipboard' button In this forum right click ina 'Post a Reply' text box and select 'Paste' Edit/remove all info on fonts and printers.

Then tell us which account number is effected. If it was the newest added mail account then it would be the highest number.