A newly created folder under Local Folders should show up as a text file in your [[Profiles - Where Thunderbird stores your messages and other user data|profile]] folder in the file explorer, as a subfolder of the ''\Mail\Local Folders'' folder. Example: if you create a folder called "test", ''C:\Users\you\AppData\Roaming\Thunderbird\Profiles\a1b2c3d4.default\Mail\Local Folders\test'' would be the file. You can view this location when right-clicking the "Local Folders" folder on the left pane in Thunderbird, which will bring you to the Account Settings dialog with this item highlighted. On the right, it is specified under "Local directory:". That however involves ''sub''folders of the Local Folders folder. I’m afraid you cannot create another "real" folder at the same level as Local Folders due to restrictions - even if you create a folder at the same level of the other folders under \Mail using a file explorer - since it is considered as an account type (see Help > Troubleshooting Information - you’ll see it listed under "Mail and News Accounts"). Therefor any additional local folder should be created as a subfolder of the Local Folders "Account". More info on files and folders and the Local Folders itself can be found [http://kb.mozillazine.org/Profile_folder_-_Thunderbird#Files_and_folders_in_the_profile here] and [http://kb.mozillazine.org/Local_Folders here]. Does this answer your question?