Close Tbird and reload it, on the next pull from server it should prompt for new password.

Yes, it prompts for the new password - twice, as it hasn't learned I've changed ips's, but doesn't like the Google password for either - imap or pop. Can't seem to find profile on C; to try to change it there. Loaded older T'bird, still had problem; tried working through Google to add Mail App so password would be connected to mailApp.

When Thunderbird started back up, I was prompted to enter my new password for incoming mail (it is an app specific password for my iCloud mail to get in Thunderbird). But I don't get prompted to enter it for SMTP mail. When I try to send mail I get a message after a long delay that says "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.mail.me.com was lost in the middle of the transaction. Try again."

Sometimes in the past, I have seen a request to enter a password for SMTP but it seems to be random. How do I request that request?

I, too, had previously gotten only "Try again."

But, just now, I tried one more time to send a test message, and this time I got a change password option for smtp. So I pasted in the new password. When I sent the change, I still got a failed to send message, but then came a successful Send. So the changed smtp password did go through. Now I can again send, as well as receive. Whee!

So keep trying to send, and maybe you, too, will get a request to enter a password for SMTP.

This request to enterwonderinggal said

When Thunderbird started back up, I was prompted to enter my new password for incoming mail (it is an app specific password for my iCloud mail to get in Thunderbird). But I don't get prompted to enter it for SMTP mail. When I try to send mail I get a message after a long delay that says "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.mail.me.com was lost in the middle of the transaction. Try again." Sometimes in the past, I have seen a request to enter a password for SMTP but it seems to be random. How do I request that request?

None of these answers work every time. Please can't you put a field in the account for a new password?

There already is a field for the password.

Click the 3 bar menu button Hover over Options and select Options when the menu appears Select Security Select Passwords Click Saved Passwords Click Show Passwords and answer Yes Right click the problem password and select Edit password

Editing doesn't work. You have to delete all passwords for that account, restart TB and when (and if) it asks, enter a new one.

Works for me just fine.

What version are you using.