From few days, maybe 10, the password is no longer accepted by the server 'imapmail.libero.it'. But when I go to the web site and open my email account I have no problems. I am lost here, can't get no hints, no signs that something has changed; when I reintroduce my account details, Thunderbird is able to find the server 'libero.it' all by itself, and I have checked on libero.it site, the procedure to open an email client with Thunderbird, nothing seems changed. I repeat: from one day to the next, apparently the server stopped accepting my password through Thunderbird, but it still accept it when I log in directly on the site. I hope somebody is able to find out what is happening here. Thank you in advance anyway for your time. I can add only that I have another email account, with Yahoo, and this one is still working without problems: Thunderbird is able to open it without any trouble. I use Linux Xubuntu 20.04 lts; just updated Thunderbird this very morning, as normal with automatic updates, no change: the password is apparently refused by the server libero.it.