WE do occasionally see folder disappear, but not in reality. A leading cause is renaming a parent folder and the sub folders get lost.

So on the help menu click on Troubleshooting information. Click on the show profile button. Open the folder mail in Explaorer No Local folders.

Is there an SDB folder that has the name of the root folder you had your mail in? IS there a file with no extension and an MSF file with the same name?. Less the sdb

Does the SDB folder contain files with mnames of familiar folders and further sdb folders?

SDB folder tell Thunderbird there are sub folders. Files with no extension are the mail for the folder of that name. MSF file are an index and not terribly important, except to make it a set of three things with the same name.

Sorry Matt but I could not understand / follow your instrux. Computer illiterate. However I found several profiles under AltData Local and Roaming and under mail in two of the profiles I found all my saved folders. WOW. Now how to get them back into the program? And again, can I prevent this disappearance by saving them under the main heading at the top (my email address) rather than under local folders.

if you are computer illiterate you best stop fiddling. Or something will really be lost.

Did you manage to find the troubleshooting information. Did you manager to click the show profile button. Did you manage to open the mail folder Did you manage to open the "local folders" folder

I can not guide you if I have no idea where I lost you.

Thank you Matt for sticking with me on this. I went to Menu - Help and when I clicked on help a web page immediately loaded - no chance to find Troubleshooting Information under help) and I could not find troubleshooting information on web page either. However, I am familiar with the profiles for TB in the AppData folder both Local and Roaming.

Under Local I found 4 profiles. Only one of the profiles (created Feb. 20, 2016) had a Mail\Local\Archives.sdb folder and lo and behold therein were the sub-folders I had created. A duplicate folder of each ended in .msf. However, they were mostly dated 6 months ago but that is probably when they were created. (More recent ones under Roaming per the following.).

Under Roaming - Mozilla - Thunderbird I found one Profile created 7/17/16. (About the time all the folders disappeared.) Under Mail - Local Folders - RP (me) Archives.sdb - Store Folder.sdb were all my folders These folders had .sdb extensions. When I clicked on one these .sdb folders I could then see all the sub-folders and each one as you said also had a duplicate .msf sub folder. This is the gold mine.

Under Roaming - Thunderbird - Profiles (not Roaming - Mozilla - Thunderbird) I found one profile with a Mail folder - Local Folder but there were no saved email sub-folders in it. However, it was the most recent profile I say here I think dated 7/23/16.

Matt, I am excited. We are getting close. What now? ps it sure would be nice to delete some of these unnecessary profiles - maybe they are what created the problem?

Menu > Help and click on the chevron Looks like > (get used to clicking > Windows 10 only shows sub menus if you click them even the start menu) or just hover to get the same sub menu

Then select troubleshooting information. (I use this because it guarantees you end up in the current profile not the one you think is the right one) It might even point to Thunderbird using the wrong profile if your stuff is not there.

But based on your further information. I think you have archived your folders (pressing A activates Archive) So go back to Thunderbird and drill down in the Archive folder under local folders. think everything will be where you left it, just with a new Root location.

Again Matt, I really appreciate you sticking with me. And how embarrassing not to realize to click the '>' to find Troubleshooting Information. I found and clicked on Show Folder and went to Windows Explorer and clicked on the Trash folder and there was the folder RP Archives.sbd and in it were all the sub-folders dated 7/23/16 - the day they disappeared. The pot of gold. The contents could not be read but if you can tell me how to reverse them (restore) back into Thunderbird all your worries will be gone and you can now get a good night's sleep without worrying about me.  ;-)

just go to the archive folder in Thunderbird.... your mail will be there.

See my email of a few minutes previous. Sorry Matt, I forgot to mention that I went to every folder in TB and the emails are not there. As I wrote a few minutes ago I found them in Trash in the profile but do not know how to get them back into the program. And of course to complicate matters I have now set up some Folders with the same name as the deleted ones. I suppose I could rename them to avoid confusion. Your valued thoughts? Ron

Matt - or someone - please do not forsake me now that we are so close to the solution. The disappeared emails have been located. Now just how to get them back into the Thunderbird program? Sooo close. Anyone care to pick up the ball is Matt has given up on me.

If you found them in the trash them they are in the program. Really you have lost me.

Thanks for responding Matt. Let me try to make it more clear. When I click on Thunderbird to open, there is nowhere in any file or folder the emails that have disappeared. None. Zip. Not anywhere.

 To find them, thanks to your help I have to go to Windows Explorer\Users\Ron Patterson\AppData\Roaming\Thunderbird\Profiles\(my profile)\Mail\Local Folders\Trash.sbd\RP Archives.sbd   -  there are the missing folders in Trash.sbd.   Again, how do I get them back into the program so that when I click on Thunderbird they are available?

troutmalt said

Local Folders\Trash.sbd\RP Archives.sbd - there are the missing folders in Trash.sbd. Again, how do I get them back into the program so that when I click on Thunderbird they are available?

My mistake, that path is to your trash folder on local folders.... so the archives should appear as a sub folder of the trash.

All of my emails disappeared yesterday when I changed from senders name to date. I now have only Dec. 27 and Dec. 28, 2016 emails. I lost a lot of important info. Thanks for your help. My mail was not in folders.