1. Forget the rot about SMTP.verizon.net. Despite good intentions I am starting to think there is no one that knows what is going on working for Yahoo/AOL/Verizon with regard to email. They just keep issuing rubbish instructions that at best is destructive and at worst damaging.

Verizon mail customers need to change the server name to smtp.aol.com. Then close the smtp server settings dialog in Thunderbird by clicking on another entry in the list like copies and folders. Then click back to the SMTP entry for Verizon to force a reload of the authentication methos list to include oAUth2.0 Once it is available, select it.

This will lead to an oAuth authentication process that loads a number of web pages from AOL asking you to authenticate. Successful completion will see you able to send mail again.

I had to fix the Thunderbird in/out AOL Verizon mail on all four of my Windows devices ( not counting my iphone...). The simple trick was to use the same generated code on all four, one by one, to receive mail, and another generated code for smtp mail, again going from one laptop to the next using same code. Now all seem to be working.

This issue is so frustrating for long time Thunderbird users. I've been using Thunderbird since vs 2.1.

Background: That said, I have had Verizon email for years, and when they bought AOL and AOL started servicing Verizon user email accounts, we had the option to keep the same account name, which some users had used for 10 years or longer. I chose to keep the same account name and have used "... @verizon.net" (and others) ever since the change. Over the past three or four years, email has been working fine.

Current problems started with the new AOL secure login passwords for EMail client software. I generated the required client password, and thought all was good, but I could not SEND outgoing emails. When I tried to send email, the error would be "could not login to Outgoing SMTP server, enter correct password". This went on for days. I've tried a number of "fixes" seen in various problem discussion threads, but nothing worked for me.

The AOL site does not address the "password" issue for the outgoing/SMTP server in any of their help documents, but they do specifically state, the Verizon.net email users must use the server "smtp.verizon.net" and not the aol.com server name. I also have an AOL.COM account (in Thunderbird) and I tried multiple configurations using the "smtp.aol.com" setting, with no success.

So, today, I generated my third (3rd) AOL mail client password, and I used that password when I received the POP-UP asking for the correct password when I tried to send an email. Entering the 3rd generated password worked to send email from Thunderbird on the Verizon.net account. I don't know why the first two generated client passwords failed to work when SENDING email, but they never worked.

Hope this helps someone else.

The simple solution is to use the AOL outgoing server settings. (SMTP): smtp.aol.com with oAuth or you can use the app password you generated in the SMTP settings

Just change the password to the app password used for incoming mail.