This is usually not a problem. In fact, I have routinely suggested deleting account info there when a user has a new password. To verify that, I just deleted account info for one of my accounts and then sent a test message and was prompted to reenter password. Try sending a message to yourself.

David, Thank you for answering. This didn't work for me. I tried sending an email to myself from Thunderbird. Then a “Sending Message” window popped up, and eventually another pop up that said “login to server smtp.mail.....failed” and it gave me the options to retry, enter new password, or cancel. When I click enter new password the window disappears, nothing appears prompting me for an new password. Then I start repeatedly getting the same pop up I get when I start Thunderbird (telling me “too many requests”) indicating my credentials failed. Hitting “cancel” just stopped the attempt to send the email, and hitting “retry” just put me back to the “Sending message” infinite loop and then another “login to server smtp.mail.....failed” box. Any other suggestions would be appreciated. Thanks again for answering. David

I would check to make sure you didn't actually set up the account twice. And recheck settings>privacy&security and, if new entries are there, I would delete again. Other than that, all I could suggest would be to remove and create new.

When you say remove and create new, what are you saying I should remove and create new, and where would I find it. I rechecked as you suggested. I don't have any new entries. I don't have any entries at all. When I go to setting>privacy&security and click saved passwords, there are no (as in zero) saved logins. And Thunderbird won't let me create a new login using my online email address because it gives me an error message that my incoming server already exists. My login isn't there under saved logins, but when I try to re-create my login with my email address Thunderbird won't create it because it thinks it already exists -- but I can't see it, I can't see or change the password, and it won't connect to my email provider's server because my provider made me change the password online and I can't update it on Thunderbird. I can't delete any entries because there are no entries. Its there somewhere, but it isn't anywhere I can find it or see it or change the password. I appreciate your suggestions. Thanks for sticking with me. David

First, I am puzzled that when you attempt to retrieve messages that you are not offered the option to enter password. That's the normal process when the entries in settings>privacy&security are removed. At this point, my approach would be this: - If IMAP account, simply delete the account and start over. nothing will be lost - if POP account, my approach would be a bit different - delete the POP account, but DO NOT tick the box to remove data. - create the account again and thunderbird will resume control of the account data FOR SAFETY, I recommend backing up the profile first. Not needed, but I like to be safe.

Actually, my chosen solution was David's first reply at 5:08AM on 11/5/2025. Details below: David, When I started Thunderbird to try your last suggestion it prompted me for a new password. In other words, Thunderbird finally did what you originally thought it would do. My saved login then reappeared and I changed the password in Thunderbird. I suspect the prompt for a new password wasn't getting through on my prior attempts because I was already logged into my email via my web browser when I started Thunderbird. Online mail was my only option to use email without Thunderbird working. This last time, when I started Thunderbird without already being in my web based email, it asked me for a password in Thunderbird and then it worked fine. This was the first time since the problem began that I started Thunderbird without already being in my email online. I never had a problem starting Thunderbird with online mail open before, but then my Thunderbird password was still valid and the server never had to come back and request password authentication. I checked after the problem was fixed, and I can now start and use Thunderbird just fine whether or not I'm already in my email account via the web. Thanks You, David

You are very welcome. :) david

I have 5 accounts on my thunderbird which I have had for many years over several computers. I can receive and reply with 4 of the accounts (3 are gmail and they work) with one of the accounts I receive email but can not reply. I used to be able to go to settings and check the password and all the settings. Something has happened in the last week or so where the message is as above "log in to SMTP server has failed " and then try new password but this does not work. I could not find the set up page I was used to. Getting old (83) and do not like changes that are not clear. I can access the email & reply by webmail but that is more complicated. I will try again to look at setting to find the passwords setting. I use a security program called MailWasher for in coming email so I do not need so much security in Thunderbird.

You can find the passwords at settings>privacy&security and clicking savedpasswords and then showpasswords.

Hi Peter.

Your issue "log in to SMTP server has failed" is not a match to what beach_boy_dave has posted about. it would be better for your to ask your own question https://support.mozilla.org/en-US/questions/new/thunderbird

Be aware that Mailwasher and similar programs can interfere with Thunderbird. Do you still have the same problem if Mailwasher is not running?