MBOX is the default file format, in which all of a folder’s messages are kept on a disk in one file. This is where the compact process comes into play, and the aim of this article is to shed light on it. The newer storage model, Maildir, has each message in a separate file.
Open the profile directory of Mozilla Thunderbird. Go to the Mail folder. Drag and drop the file from its remote location to your Local Folders folder, for example, Archive Open Mozilla Thunderbird. The archived folder should appear in the Local Folders list under the Folder list.
To begin, open the Thunderbird application. Then select the threaded folder. Finally, click View and Sort By Unthreaded to list them in chronological order.
All of your permanently deleted emails are permanently deleted when you compact. The files are overwritten so that they only contain the email you actually have. As a result, the file size is smaller and it is easier to access since the messages are closer together.
To reach the setting, go to “Options” from the menu. Uncheck “Compact all folders.” It will not bother you again for an automatic compact in the Advanced > Network & Disk Space tab.
