Let's back up.

1. The fact a web password works on the web is in no way relevant when it comes to the email server and the use of email ports. If in doubt about that have a look at the ATT/Yahoo offering which requires a mail key not the users password.

2. Deleting a non functional account actually make recovery much more difficult. Previously you had an account that did not get mail. Not you have no account, so we are trying to add it back. It did not work before, there is nothing to suggest anything is going to change, so it probably will not work once added again.

3. You removed the incoming account. Did you remove the outgoing server(SMTP) for the account? I would guess not as adding the account again is failing, probably because there is an existing SMTP account with the same name.

Note the vast majority of "failure to get mail" issues stem from antivirus products. This is closely followed by VPN's and then we get to passwords being invalid. It is way down the list and only once have I seen the password as set not being accepted by the providers server (it was Microsoft and they required ANSI characters in passwords using mail clients, but not web access) On rare occasions the issue are incorrect settings in Thunderbird, but you are saying you have already ruled that out. This forum has had a spate of folk complaining about certificates post update and they all appear to use Norton antivirus do you?

I understand that you are frustrated that I did not troubleshoot the way you would have. I have in the past had some success with removing accounts and re-adding them. That is why I did that.

Can you tell me why ONE of the TWO mail accounts on my server works? The settings for incoming and outgoing mail servers are identical for both accounts. The only differences are the username and password. Domain is the same.

As far as I can tell the way a user is instructed to remove an account does not allow for the SMTP server to be saved. Can I check this in a configuration file somewhere?

I am using Zonealarm, not Norton. I have some 30 years software engineering experience and though I am unfamiliar with the guts of mail clients I can potentially help you diagnose if you can explain what you need.

Can you tell me why ONE of the TWO mail accounts on my server works? The settings for incoming and outgoing mail servers are identical for both accounts. The only differences are the username and password. Domain is the same.

No I can not. But I do not have the benefit of knowing very much about your setup or the accounts your are connecting to. But as each incoming account has one or more outgoing accounts associated with it (usually one per identity) they should not be the same as the incoming account

Perhaps if you were to share the error oyu get when that account does not work I might have a chance at doing more than guessing. But first you need to get to the point oyu have a non working account to get that error.

As far as I can tell the way a user is instructed to remove an account does not allow for the SMTP server to be saved. Can I check this in a configuration file somewhere?

You could check in outgoing servers (SMTP) in account settings for an entry still existing. As SMTP servers are allocated on a per identity basis. A single incoming account can actually have multiple SMTP servers associated with it. As far as I am aware removing an incoming account has no impact on outgoing server entries as they have their own add and remove buttons in the account settings panel.

I am using Zonealarm, not Norton. I have some 30 years software engineering experience and though I am unfamiliar with the guts of mail clients I can potentially help you diagnose if you can explain what you need.

If you are still messing with the new account wizard you can get much more explicit information on the process by enabling logging before you try and use it. I wrote some basic instructions here years ago. https://thunderbirdtweaks.blogspot.com/2021/10/logging-new-account-wizard.html

I am not saying they will provide an automatic answer, but having a whole log may well help.

Fundamentally I hate antivirus products. I find they generally cause as much grief as they are supposed to prevent. When I got this PC a couple of years ago and stopped running windows servers I bit the bullet and simply went with windows defender instead of the multi seat paid solution I was using on the servers. The primary change I noticed is I don't get popups all the time about questionable JavaScript in web pages tracking me. So I have a jaded view reinforced by the woes of folk that appear in these forums with regular issues caused by antivirus products and their self signed certificates and good intentioned blocking of unknown software (the latest update) at the software firewall. I doubt that in this instance it is the issue, but it might be. This is why we have what are basically standard diagnostics in a canned text form, which I will follow up with.

Could you please do the following?

1. Open the menu > Help > Troubleshooting Information, then click Copy text to Clipboard.
2. Go to https://pastebin.mozilla.org/, paste the clipboard by right clicking in the large text area, select paste from the menu, change the retention period to expire in 28 days, use the Paste Snippet button to create a page containing your info, then copy the resulting URL (address) of the page created.
3. Open a reply to this post, and paste the URL to your troubleshooting information you just copied.
4. Please also provide results for the following test on your system
   • Does Thunderbird work as expected in Thunderbird troubleshooting mode?
   • Does Thunderbird work as expected with your OS started in safe mode with Networking. Instructions for each operating system: Windows 10/11, Windows 8, Windows 7, OSX

Thanks for your reply. I started working through the list of things you gave me to do. When I restarted Thunderbird in Troubleshooting mode I was able to successfully create the account I wanted. PROBLEM SOLVED.

So it seems that one of my add ins might be the culprit. The ones I use are Cardbook, Enigmail and Provider for Google Calendar. I also use the Australian English Dictionary but no other themes etc.

In case you want to do some more debugging, here's the link to the Troubleshooting Information: https://pastebin.mozilla.org/NyrCJS2E

I tried using your instruction about the config editor. Neither of these two keys exist: mail.wizard.logging.dump mail.wizard.logging.console Is it safe to add them? If so, can you tell me the valid settings for these? I know we need "all" but what setting should be used for no logging? Is it "none"?

So it seems that one of my add ins might be the culprit. The ones I use are Cardbook, Enigmail and Provider for Google Calendar. I also use the Australian English Dictionary but no other themes etc.

Enigmail has not been an addon for Thunderbird for a number of years and the the data you uploaded confirms you do not have that addon installed.

In case you want to do some more debugging, here's the link to the Troubleshooting Information: https://pastebin.mozilla.org/NyrCJS2E

I tried using your instruction about the config editor. Neither of these two keys exist: mail.wizard.logging.dump mail.wizard.logging.console Is it safe to add them? If so, can you tell me the valid settings for these? I know we need "all" but what setting should be used for no logging? Is it "none"? </blockquote>

You just reset them to default when you are done logging the process and the next time Thunderbird restarts they will be removed from your stored preferences. Thunderbird only stores non default values in preferences.

If your ZoneAlarm has some sort of scam or spam tools you might want to try disabling those as they will also be disabled by Thunderbird in safe/troubleshooting mode. (those type things are usually injected into the running Thunderbird process as an addon.)