the settings page needs it to reveal saved passwords, which is a catch 22.

To reveal the saved passwords Thunderbird will prompt you for the Primary Password. So there's no catch 22. https://support.mozilla.org/kb/protect-your-thunderbird-passwords-primary-password

If your password is not working, you should receive a prompt that password doesn't work with a button to enter new password. The settings page would need to show you your current one if you are wanting to see what is stored.

Thank you for your replies. I tried the Mozilla password on the Windows Security Page for Mozilla Thunderbird to very my identify to reveal the saved passwords but it continues to say that the username or password is incorrect. Is there another password I should be using?

Making some progress. I am able to find an open saved logins and see some passwords. However when I copy and try to paste the indicated password (a 640 character long string), it doesn't work. Is there a translator for it? If I remove it, can I simply replace it with a memorable string? As before, thank you for your consideration.

passwords that long are 'app' passwords and are created by the email host. It may help to know your email provider, such as Gmail, Outlook, etc.

Making some progress. I am able to find an open saved logins and see some passwords. However when I copy and try to paste the indicated password (a 640 character long string), it doesn't work.

Presumably your account uses OAuth authentication. If so, then Thunderbird stores an authentication token instead of the actual account password. If you forgot your account password check with your email provider about password recovery options.

I spent over an hour with a Comcast technical support person in the Philippines but with no success. It has been escalated to the next level for reply sometime in the next 3 days. If they can provide me with a solution, I will post it here. In the meantime I can check my email on their website but can not access it directly in Thunderbird. Might reinstallation help or would that lose all settings?

Rather than actually escalating it and contacting me, the ticket was closed out, saying this is a Thunderbird problem. Today's half hour call to them was no help.

I am dead in the water and my mail is rapidly filling up the Comcast server and will stop shortly. It appears that I paid $148 last year through PayPal to help maintain Thunderbird. Can I get some help resolving this problem?

These two articles may help, but I'm not familiar with Comcast. https://www.xfinity.com/support/articles/third-party-email-access https://www.xfinity.com/support/articles/email-client-programs-with-xfinity-email

Ok, I am puzzled.

For over a week the same password has been rejected. I tried again last night, only to have it rejected as usual. However, this morning out of curiosity I tried it again, only to have it accepted and nearly 500 messages have downloaded so far. I have made no changes to the system. Any idea what happened overnight? Did one of you work your software magic long distance? If so, thank you. ;-)

Well, it worked for a while, but at 12:22 pm today it stopped working. Comcast continues to say it is Thunderbird's problem, not theirs. I have tried restarting the computer twice but no change.

Thanks for the articles.

Well, you won't be the first person to share that Comcast blames Thunderbird. I will try to find someone who knows xfinity better.

First, what are your settings? According to Xfinity, they should be:

incoming IMAP: imap.comcast.net, 993, SSL/TLS, OAuth2 authentication, email address

outgoing SMTP: smtp.comcast.net, 587, STARTTLS, OAuth2 authentication, email address

https://support.mozilla.org/en-US/questions/1437228#answer-1631854

Check that cookies are accepted in TB (not browser) Settings/Privacy & Security. Remove entries for the account from Saved Passwords, restart TB, enter the account password in the OAuth window when prompted to allow access.

If it still doesn't work, there might be interference from an antivirus (if it's not the built-in Windows Security) or VPN, if in use.

Excellent advice!

I changed settings that had worked for the last decade from mail.comcast.net (port 995) to imap.comcast.net (port 993) and turned off Norton VPN to solve the "Excessive failed authentication, ESMTP server temporarily not available" problem. Things seem to be working so far :)

I am not sure why Comcast could not have shared these settings 10 days ago but I am very thankful for this communities support and wisdom.

Note that if the account was mail.comcast.net on 995, it was a POP setup, so to change to IMAP, the account has to be re-added as IMAP. But if you want to keep it as POP, just change the server to pop3.comcast.net, 995, SSL/TLS, OAuth2, email address.

https://www.xfinity.com/support/articles/switch-email-pop-to-imap

Thanks to your help, email is now coming in regularly, but the original visible file structure has been lost. It shows only 9 files where there are over 7000 subdirectories.

I rebuilt the Sent file as it is one of the visible files and it appeared to reindex the 46K messages but they remain inaccessible. The rest of the directories are not visible to allow possible rebuilding. I tried reinitiating the 14 GB global-messages-db.sqlite file (worked before) but it stopped at about bringing in 4 GB after a day. Deleting the Inbox.msf file made no difference. The actual 229 GB files appear to be still there, just not accessible. Any ideas how i can revive the file system or should I start a new note?

Thank you for your consideration.

turned off Norton VPN to solve the "Excessive failed authentication, ESMTP server temporarily not available" problem.

Your miraculous fix and sudden lack of fix will be a direct result of your decision to use a product with a Norton brand. Whilst I have issues with the standards of "support" offered by all ISP these days, the problems caused by antivirus/security software are legend and the ISP is no more able to diagnose them that the mail client developer is.

Even the regular contributor to this forum that does use Norton has had to turn off a number of "features" including VPN and modify others to make Mail simply work as it is designed to. When I have set up Thunderbird for friends I have found those using Norton product also needed something called SONAR turned off or the new account wizard was crippled with errors.

Personally I just use Windows defender and have none of these issues that come with paying for security software as it does not see the need to scan email at all. Microsoft is apparently of the opinion that there are plenty of opportunities to scan for issues with email other than in transit.