Passwords - if stored - are located here: Settings > Privacy & Security Scroll down to 'Passwords' section Click on 'Saved Passwords' Click on 'Show Passwords' You may get asked for a password in order to see them. If you had previously setup 'Primary Password' : The 'use Primary Password' checkbox would have been selected and you created a specific 'Primary Password' (nothing to do with mail account passwords) in which case enter the Primary Password. If you did not create a Primary Password: When you start up computer, you would have been asked to enter a User Account or Microsoft account password - this is the password you need to enter. Then you get access to see stored passwords. If there is nothing in the Saved Passwords - it is completely empty of anything: Do you have any Anti-Virus or other clean up software like CCleaner or WiseCleaner installed because they may have settings to clean up certain files like session or passwords. It is recommended that to prevent this sort of nuisance occuring you do not allow those clean up programs to access any profile folder nor auto fix any file. If you get prompted to enter a mail account password then you need to Enter the relevant mail account password and select the 'Remember Passwords' checkbox before clicking on OK. Please post additional information such as: What OS are you using ? What Thunderbird version are you using? What servers are you talking about ? gmail, yahoo, outlook, comcast etc ? In Thunderbird * Help > Troubleshooting Information * Scroll down to 'Mail and News Acounts' section * Copy all data and post into this forum question - or post an image showing data. Do you have the Thunderbird profile stored in the default location ? Did you download Thunderbird from the official Thunderbird webpage: https://www.thunderbird.net/en-US/thunderbird/all/ Did you get the installation from another location such as Windows App store or Flatpak etc?