Hi Elliot, Let's try removing the password you have saved, which will force Thunderbird to prompt you to input your new password.

1. Go to [=] > Options > Options > Security > Passwords, then click Saved Passwords.
2. Click Show All Passwords and confirm.
3. Take a screenshot of your passwords as a backup.
4. Click the Remove All button.
5. Restart Thunderbird, then enter your passwords when prompted.

I had tried that but it didn't work. But I did stumble onto a solution.

When I put in a new password at the Gmail website an interesting thing happened when I tried to login using Thunderbird on the 2 computers that were previously successful. Each brought up a gmail login page in a browser window to authenticate. Then each computers Thunderbird could access gmail without doing this. BUT the computer having the difficulty was using a different browser as it's default. I think it was firefox. When I changed the default browser to chrome the problematic computer was able to bring up this login page from Thunderbird and it was able to access my email.

So, to interface with gmail for the first time or after a password change it appears that the default browser must be at least Chrome. I'm not sure if any others work.

Thanks for your help,

Elliot

Hi Elliot, It shouldn't bring up the browser at all. A separate Thunderbird pop-up should take you to the Gmail website. Here's a video of Gmail setup:

In any case, I'm glad you solved the problem, and let us know what fixed it. That information should come in handy if someone else has the same issue.

Well, it may have been coincidental that changing my default browser happened before I was able to sign into gmail with Thunderbird but what was missing in my attempts to do it on this computer was that Thunderbird pop-up. So, something occurred to allow it to popup. Not sure why.

Elliot

I am having the problem of adding GMail account to Thunderbird. I was previously using GMAil in Thunderbird, but had to do a "Fresh Start" on my Windows 10 to eliminate a "Blue Screen" problem. I reinstalled Thunderbird and added 2 of my accounts, but I can not get GMail to add. I follow the instruction in your video, step by step, and everything goes as shown until after I click Allow in the Google screen. The google screen goes and I am left with the 'Mail Account Setup' window in Thunderbird, with Checking Password and the rotating green circle, which continues to rotate indefinitely.... My only functional option when I get this is to let it run, and it will go for hours, or hit 'Cancel'. If I do manual config and hit Re-test, it shows the setting found by the given server. If I hit Done, a window opens and says "Incoming server already exists." This does not help me... So my only option is to Cancel, and I get no new account added....

Hi Michael, Your issue may have similar symptoms, but it is likely a different cause/solution. You should use https://support.mozilla.org/en-US/questions/new where volunteers can get more details about your setup.

Because this thread is solved and more people might start using it for their own questions, I'm going to lock it.