<p>To open this assistant again in the future from the main window of <i>Thunderbird</i>, choose <b>[[!img lib/open-menu.png link="no" class="symbolic" alt="Menu"]] ▸ Account Settings</b> and then, from the <b>Account Settings</b> dialog, choose <b>Account Actions</b> ▸ <b>Add Mail Account</b>.</p>