Spun off from bug 524868, this applies to SeaMonkey only as Thunderbird 3.0 has redesigned the account wizard. During the initial setup of a mail account, attachment 417410 [details] dialog is shown for user names (ingoing and outgoing servers). It is now necessary to clear authentication for an SMTP server which doesn't require it, otherwise an error is reported and the message not sent (bug 524868). When clearing the lower field for the outgoing server, it is nevertheless filled with the user name of the incoming server, as shown on the final page of the account wizard. The user has to manually clear the "Use name and password" in the SMTP setting after the initial setup to avoid the error. Instead, clearing the user-name field should imply the equivalent of "Use name and password" not checked (auth_method=0).
Are you sure because of the password? Aren't they stored only in the Password Manager?
You don't enter the password in SM's account wizard; it's only asking for the user name and the user is prompted for the password the first time he or she connects, then it can be stored in the password manager. I'm talking about what's happening way before that, i.e., a user name is always set by the account wizard even if you explicit remove it in that dialog.
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