The hard disk of my computer was not too well, I bought a new computer and transferred my Thunderbird profile and the Local Folders (which were not within the profile folder on my previous computer). On the new computer, the Local Folders are within the profile folder. When using Thunderbird, all seemed OK, except that some folders in Local Folders were missing or empty, which they were not on my old computer. Investigating the Local Folders showed that some folders missed their foldername.msf file, their foldername file (no extension) and/or possibly their filename.sbd folder. By creating empty files/folders with the correct name and removing msf files where all else was present for the folder, I managed to regain access to some folders, but not all. When I search for words that occur in folders that are now empty or missing, I get results with messages that are (or should be) in those folders, but I cannot open/access these messages. What else can I do to regain access to the missing folders and messages, even just recovering (as much as possible of) the contents of the message would help me a lot. The old hard disk appears to have died during / after transfer of my files and folders. It is now completely inaccessable and should be considered as a total loss. Backups miss the same files/folders, so the corruption was a lot older than I thought - but Thunderbird had full access to the folders that are now empty right until I transferred all my files from old to new computer (with rsync via ssh). General information : I use Thunderbird for decades, O/S is openSUSE (at least 25 years) now at LEAP 15.3.