After set up, go to <b>≡ > Account Settings > Server Settings</b> and make sure the <b>"Leave messages on server"</b> option is <b>checked</b>, and the <b>"For at most [X] days"</b> option is <b>unchecked</b>.
完成设置后，进入 <b>≡ > 账户设置 > 服务器设置</b>，确认<b>勾选</b><b>“把消息留在服务器上”</b>，且<b>不要勾选</b><b>“至多不超过 [X] 天”</b>。