When you allowed Thunderbird to update to version 91.4.1, what occurred immediately afterwards ?

Did you seem to completely lose everything - all mail accounts, address books etc etc? Did Thunderbird ask you to create a mail account as if it was using a completely new Profile ?

Did you attempt to see if the original profile was available by doing the following: In Thunderbird Menu app icon > Help > More Troubleshooting Information Under 'Application Basics' section - near the bottom locate 'Profiles' and click on 'about:profiles'

It should open in a new tab. It should list all the profiles. Each profile would have a name eg: Profile : default Each profile will contain information such as: Default profile: Yes or No Root directory: this is the name and location of the profile where emails are located local directory: directory created and used by OS to faciliate runing of program profile. Below will be some buttons. You can set a different profile as default by clicking on 'Set as default' and then you can open that Profile by clicking on the 'Launch Profile' button

Did you locate the original profile or not ?

Maybe you updated and it was just the 'address books' not visible and at the same time you could not send emails because the 'send' button does not appear to work?

If this is the case then I need to know what is in the error console ? Please supply information. control +shift +J What is in error console ? - post an image of the contents of the error console.

It would also be helpful to know the following information about 'prefs.js' files, just in case you really only have one profile but Thunderbird lost access to the data. In Thunderbird Menu app icon > Help > More Troubleshooting Information Half way down - 'Profile Folder' - click on 'Open Folder' button

profile name folder opens in a new window showing contents.

Exit Thunderbird now

Make sure the view is showing 'details' - name, modified date, type, size columns Scroll down to see 'prefs.js' file Do you see more than one - maybe with additional number like 'prefs-1.js', 'prefs-2.js'  ? Do some have a zero size ? Please post an image showing all the 'prefs' files.

Open 'prefs.js' file using a simple text editor like 'Notepad' Scroll down to thew section shwoing 'ldap' references. Post an image showing all ldap references.

If you have another 'prefs-n.js' file - locate the one with the highest number - open it and locate the ldap references and then post an image of what you see - make sure I can see directory info so I know which file is which.

I asked you to go to this location - get more info whilst in that location:

In Thunderbird Menu app icon > Help > More Troubleshooting Information Half way down - 'Profile Folder' - click on 'Open Folder' button

profile name folder opens in a new window showing contents.

Group/sort by 'Type' so all the 'sqlite' files are together. Post image showing all the 'sqlite' files.