Account name

Insert here the name of the account: this is normally the same than User name, but it doesn't have to, and is the value you'll have to insert in your e-mail client as a mail user to check.
For example, if you've user myself on an external mail server, you can put myself_filtered, any other significant name, or just myself here and in the user name of the email client (as long as you'll do that in both places), while in User name dialog you must input myself.

Clicking Cancel here or in any of the following screens will bring you to a dialog where you can insert all data at once, as opposed to insert them one by one with a detailed explanation.