Scenario - password was changed on remote mail server (from a different computer). Authenticated SMTP mail send was attempted from this computer (without changing the password stored in Mozilla). Mozilla kept attempting to authenticate (and did not give an option to change the password). Session capture attached below. Unchecking and rechecking the Use Username and Password did not clear the problem. Clearing the password under managed stored password did clear the problem and allow Mozilla to ask for the new password. This is my first bug report, hope I did it right. -Rick... 220 mailshell.com ESMTP EHLO afterburner.net 250-mailshell.com 250-AUTH LOGIN CRAM-MD5 PLAIN 250-AUTH=LOGIN CRAM-MD5 PLAIN 250-PIPELINING 250 8BITMIME AUTH PLAIN AHJueW1hbkBhZnRlcmJ1cm5lci5uZXQAYWZ0ZXJidXJuM3I= 535 authorization failed (#5.7.0) AUTH PLAIN AHJueW1hbkBhZnRlcmJ1cm5lci5uZXQAYWZ0ZXJidXJuM3I= 535 authorization failed (#5.7.0) AUTH PLAIN AHJueW1hbkBhZnRlcmJ1cm5lci5uZXQAYWZ0ZXJidXJuM3I=

I have the same problem. I have changed the SMTP password on the server and now I can not change it in Mozilla. I can not even cancel the username since it somehow gets remembered b Mozilla even if the setting is unchecked. I am using 1.2b on Win98 but this used to be the problem since 1.1a and maybe even before that.

Isn't this dup of Bug 155172 ?

Yes. *** This bug has been marked as a duplicate of 155172 ***