Did you just update Thunderbird ? If yes, what was old version and what is new version ?

Try this: Menu app icon > Help > Troubleshooting Information Under 'Application Basics' near the botton - click on 'about:profiles' It will open in a new tab and list all profiles. I'm betting the current profile name set as default is not your original profile. Locate old profile and below it you should see 'set as Default' - click on that button, then click on 'Launch Profile..' button which should open in a new Thunderbird window. Finally close the original Thunderbird wndow.

Thanks for your answer.

No, I haven't updated Thunderbird, but perhaps it was automatically? My actual version is: 78.11.0 (64-Bit)

I do not really understand what you mean with "old" and "new"profiles. But if I follow your instruction I found this: (please take a look on the attached screenshot).

I noticed something else: When I search for an old email in thunderbird, I can see it in an overview. However, I can neither open this mail, nor forward it, nor view it completely. Maybe this is an important hint for you?

Best regards Alexandra

The image shows you only have the one profile name folder. Thunderbird has opened on that profile name folder, so this tells me the 'profiles.ini' file knows about the profile. The search results tell me the global database file is accessible and working, but cannot find any account data. This makes me think something has happened with the 'prefs.js' file as that contains all the data which says where all the mail accounts are located.

Menu app icon > Help > Troubleshooting Information Under 'Application Basics' about 8th in list - Profile Folder - click on 'Open Folder' (Ordner offnen) A new window opens showing the contents of your 'profile name ' folder called s2uonsv5.default

Exit Thunderbird now this is important.

Scroll down and look for 'prefs.js' file - this is the file currently being used and I think it is not good - perhaps it has a low size. Do you see more of these files with a number like 'prefs-1.js', 'prefs-2.js'? The one with the highest number will be the one you previously used. If yes then do this:

• Rename the 'prefs.js' to a number much larger than you have in the list eg: 'prefs-20.js'
• Then locate the one with highest number eg: 'prefs-5.js' it should have a good size eg: 78KB
• Rename that 'prefs-5.js' to say 'prefs.js'

Then start Thunderbird.

HI, sorry, I'm ill and so I answer delayed.

If I follow your instructions, I only have one prefs.js file. No others in this directory.

I then searched the entire computer and found a few more, but in a different directory.

Can I now simply take the file with the last date, e.g. prefs-3.js, and continue as you described? What does the modification date mean? Is this the status of the emails from 29.07.2021 and everything after that is missing?

I am really very grateful that you are trying to help me.

Best regards Alexandra