re : ''Is thies eventually a newe trick of the secret service/national security association, to disturb foreign citizens or to exclude any of their activities?'' Seriously. I know you must be infuriated because it would annoy me. But this has nothing to do with your issue, so please stop ranting as it does not help. re ;''Who will indemnify me of the heavy losses (the disparition/disappearance) of all my data with you (Thunderbird). '' That is down to you. It's your computer and you are using a free product. Are you aware of the term 'backup' and do you create backups? However, at this point, it is still unknown if the data is really lost or just not displaying. To try and sort out your issue. Help us to help you by supplying some information. work through each request for info and post info as required. Posting images to help explain\clarify is good. It can also help save time typing. What do you see in the Folder Pane? Can you see the mail accounts listed? Can you see folders? suggest you post an image so the forum can see the problem. At this point, I do not know if Thunderbird has lost track the profile or mail accounts, so need you to follow these instructions to post information. Can you check to see how many Profiles you actually have? Make hidden files and folders visible. * http://kb.mozillazine.org/Show_hidden_files_and_folders in thunderbird Help > Troubleshooting Information Click on 'Show folder' button a new window opens showing the contents of your current profile folder name. In the directory click on 'Profiles' - see image below. In my example there is only one profile folder name called xxxxxxxx.default, and I'm open on that profile folder name (where the x's are letters and numbers). How many profile folder names do you see? Tell me the profile folder names or post image. select a profile folder name - make a note of its name. Tell me what you see or post image. Do this for all profile folder names. If you use a pop mail account , click on 'Mail' folder You should see 'Local Folders' and other mail account names. If you use IMAP then click on 'ImapMail' folder Tell me what you see or post image. Click on mail account name. do you see files that have same name as your missing folders? Do they have a good size? Please go up the directory to the 'Thunderbird' folder. It will have a 'Profiles' folder. It will also have 'profiles.ini' file. Open the 'profiles.ini' file using Notepad and post an image of its contents or copy paste the info.