Hi there, i try to describe my problem as good as i can, i am no native english speaker, so sorry for any confusing phrases :) '''What is my acutal problem?''' When i open Thunderbird it asks me to type in the password for the account. If i type it in without checking "save password" everything works. When i check that Thunderbird should save my password, Thunderbird is trying to send the login information, but after some time (about two minuets) i get a timeout error while trying to reach the mailserver. I am able to login and work with webmail, i contacted the hosting provider, we double checked all settings in Thunderbird and he also checked if any IP of me is blacklisted or something, but everything is fine. '''Since when does this happen?''' I am self employed and i am providing IT support for customers. Yesterday i got this new customer who said he can't receive mails anymore. His installation of Thunderbird was really old (version 45.x), so first things first i updated the installation to the recent version. When i first opened the updated Thunderbird the password prompt appears and the problems begin. '''What i tried to fix the problem''' I did some research. I searched for pkcs11.txt inside the profile, but there was none. After that i looked for key3.db and key4.db files, i found both and moved them both to a backup-folder and started Thunderbird again. key4.db is created new, but that does not fix the problem. I can't find any more related topics to my problem, so maybe some of you have any idea. As i said, when i don't check the box to save the password, Thunderbird is working fine without any problems. Thanks in advance for any help, greetings from germany Christian