Know about MBOX File extension

Introduction to MBOX File Extension

MBOX File

While using an email client there arises a need for storage of email messages or folders containing messages, contacts etc so, the format in which applications save the email messages in the physical hard drive is known by extension (.mbox).
  MBOX is basically an extension used for holding collection of email messages.  It is possible to store all email messages in one file and index them and they are called as databases, but in this process we need a lot of hard disk activity which makes it slow .So we can store our emails using another approach that is creating a file for each mailbox and storing all the messages and information in them.

• MBOX Format:

All of the messages are linked together and stored as a text in a single file. Starting of each message is done by “From” keyword .From is followed by a white space character, called a ("From_ line" or "'From ' line" or simply "From line”). If this sequence ("From ") at the beginning of a line and followed by an empty line or is at the top of the file, then we have the beginning of a message.

• Modified MBOX

Some e-mail clients use a different type of the MBOX format for their mail folders.
Eudora uses an mboxo variation where a sender's e-mail address is replaced by the constant string "???@???". Most MBOX clients store incoming messages as received whereas Eudora first separates out attachments present in the message and then stores the attachments as separate individual files in one folder.

Message Decryption

How a message is read stored in MBOX extension

1. An email client reader scans throughout MBOX file looking for From_ lines.
2. Any From_ line marks the beginning of a message.  
3. Once the reader finds a message, it extracts an (possibly corrupted) envelope sender and delivery date out of the From_ line.  
4. It then reads until the next From_ line or scans till the end of file, whenever From_ comes first.
5. It removes the last blank line and deletes the quoting of >From_ lines and >>From_ lines and so on.

Email clients that support MBOX File Format:

E-Mail Clients

• Mozilla Thunderbird:-
• GNU Mail:
• Mozilla Suite:  
• Netscape:  
• Mahogany:  
• Mulberry:
• Apple Mail:
• Spice bird mail:  
• Microsoft Entourage:
• The Bat! :
• Turnpike:
• Mail copa:
• Chaos Intellect:  
• Pocomail:
• Eudora email:

MBOX Files rarely face issues related to corruption or damaged file data. Usually while relocating files from one source to another tampers the file and makes it inaccessible to e-mail clients. Third party applications such as Free MBOX Viewer, troubleshoots all the problems related to MBOX files. For Similar products and other powerful file viewers; visit Freeviewer, a collection of free file viewers.