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*Details: File format summary



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Other names  
Identifiers MIME:  application/mbox
PUID:  fmt/720
Classification Text (Structured)
Description MBOX is a commonly used format for storing email messages. MBOX files may be produced by a variety of email clients, however these are often not mutually compatible. MBOX databases typically contain a linear sequence of electronic mail messages. Each message begins with a separator line that identifies the message sender, and also identifies the date and time at which the message was received by the final recipient (either the last-hop system in the transfer path, or the system which serves as the recipient's mailstore). Each message is typically terminated by an empty line. The end of the database is usually recognized by either the absence of any additional data, or by the presence of an explicit end-of-file marker. Attachments within MBOX files are typically base 64 encoded, allowing binary data to be transferred over media designed to deal with textual data. Due to the variety of MBOX structures, it is not currently possible to produce an authoritative signature for the format.
Byte order  
Related file formats None.
Technical Environment  
Supported until  
Format Risk  
Developed by None.
Supported by None.
Source Digital Preservation Department / The National Archives
Source date 12 Feb 2015
Source description  
Last updated 12 Feb 2015
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