All folders and messages are stored in a directory named Messages in the user's home directory. Folders are directories that contain message files and are only recognized by VMail as a folder if they contain a header file (.hdr). The header file contains a single line of parsed header information for each message in the folder. If the message files are changed, deleted, or new ones are added, the required messages will be reparsed and a new header file written. Folders can be nested by having "/" characters in the name. Each message is stored as a separate file in the folder directory with the name msg.*.
When a message is opened for the first time, a msg.*.body file is created that contains the viewable body part of the message with all attachments removed. If there are any attachments, a list of them is kept in msg.*.attach. Each attachment is named msg.*._attachment_name and is stored in its unencoded form.
If the message was encrypted, a file named msg.*.crypt is created. After the body is shown in the Message Window, the msg.*.body and all attachment files are deleted so that no "unencrypted" parts of the message remain on disk. The msg.*.attach file is kept to avoid unnecessary repeated decryption.