Sustainability of Digital Formats: Planning for Library of Congress Collections

Introduction | Sustainability Factors | Content Categories | Format Descriptions | Contact
Format Description Categories >> Browse Alphabetical List

cc:Mail Archive Email Format

>> Back
Table of Contents
Format Description Properties Explanation of format description terms

Identification and description Explanation of format description terms

Full name cc:Mail Archive Email Format

CCA is the archive format used by the obsolete cc:Mail email system popular in the mid-to-late 1990s. CCA files contain all email message components, including attachments. The cc:Mail software program was a MS-DOS based store-and-forward LAN based email system which was eventually absorbed into Lotus Notes. See Notes for more information.

Relationship to other formats
    Affinity to IMF, Internet Message Format.

The limited available documentation for cc:Mail does not state an explicit relationship to IMF but IMF defines the ASCII-based syntax required by SMTP for all email message bitstreams used by message transfer agents (MTAs) when moving messages between computers. Comments welcome.

Local use Explanation of format description terms

LC experience or existing holdings The Library of Congress has a small number of cc:Mail files in its collections.
LC preference See the Library of Congress Recommended Formats Statement for format preferences for Email messages.

Sustainability factors Explanation of format description terms

Disclosure Little documentation available about CCA is available. The majority of the documentation refers to the cc:Mail email platform.
    Documentation There is no publicly available specification that defines cc:Mail as an archive format. Comments welcome.

The cc:Mail system provided native email clients for DOS, Microsoft Windows, OS/2, Macintosh, and Unix (the MIT X Window System under HP-UX and Solaris). cc:Mail allowed client access via native clients, web browsers, POP3 and IMAP4. cc:Mail provided the first commercial web-based email product in 1995.

According to Computerworld on Jan 25, 1999, there were 14 million cc:Mail users at the end of 1997. This dropped by about 50,000 users per month from 1997 - 1999 with the development of Lotus Notes.

    Licensing and patents

CCA is an obsolete format no longer supported by any current email platform. There are no known patents. Licenses, if they existed when cc:Mail was in active use, are no longer valid. Comments welcome.


CCA files are US-ASCII text so are accessible through plain text processing tools.


All ASCII-based email message bitstreams, including CCA, follow the IMF syntax which includes well-structured header fields.

External dependencies None because CCA is no longer in active use. See Notes for more information about software compatibilities.
Technical protection considerations None

Quality and functionality factors Explanation of format description terms

File type signifiers and format identifiers Explanation of format description terms

Tag Value Note
Filename extension cca
Internet Media Type application/octet-stream entry's on cc:Mail lists cc:Mail's MIME type as application/octet-stream, the default for all binary data streams especially those without a file extension. However, all email formats based on RFC 822 (and it's successors RFC 2822 and RFC 5322) have the MIME type message/rfc822 See IMF for more information. Comments welcome.

Pronom PUID See note.  PRONOM has no corresponding entry as of March 2023.
Wikidata Title ID Q122047541
See for cc:Mail Archive Format.

Notes Explanation of format description terms


According to Unkroth, Lotus cc:Mail used the address format <user> at <post office> (note that "at" is not a synonym for the @ sign, and <user>@<post office> would form an invalid address). The cc:Mail formatted addresses needed to be translated to conform with the RFC 822 model of <user>@<post office>. Comments welcome.


There's little history of the CCA archive format but Wikipedia provides a time line for the cc:Mail software platform: "cc:Mail was a store-and-forward LAN-based email system originally developed on the Microsoft MS-DOS platform by Concentric Systems, Inc. in the 1980s. The company, founded by Robert Plummer, Hubert Lipinski, and Michael Palmer, later changed its name to PPC Systems, Inc., and then to cc:Mail Inc."

The cc:Mail platform was acquired by Lotus Development in 1991 and Lotus itself was acquired by IBM in 1995. Lotus attempted to migrate cc:Mail customers to Lotus Notes but the CCA format was not supported in Lotus Notes. The final version of cc:Mail was 8.5 and was released in 2000. The cc:Mail email platform was withdrawn from the market in October 2000 and all cc:Mail development ceased the following January, with telephone support ending in October 2001.

The two major contenders for cc:Mail users, Microsoft and Lotus, both developed tools to migrate CCA data into new platforms. Lotus's attempts to move cc:Mail customers to Lotus Notes met with limited success, because of early challenges in the area of coexistence and migration between cc:Mail and Notes and because Lotus was focused on groupware rather than simple email. Microsoft, which provided a simpler migration path and a more focused solution (email), succeeded in winning the majority of the cc:Mail installed base in the United States.

Microsoft created a utility called "Exchange Server Importer for Lotus cc:Mail Archives" (; this link was no longer working when checked in January 2022), sometimes also referred to as "Microsoft Importer for Lotus cc:Mail Archives," to import CCA data into Outlook PST files. The cc:Mail Archive Importer for Microsoft Exchange Server created a folder called cc:Mail Archives and a subfolders for each archive file selected for conversion. The ASCII message files, including header information, were translated to PST format before ingest. However, the Microsoft importer did not import rich-text features supported in later versions of cc:Mail. Style characteristics such as fonts and highlighting are not retained in the imported messages.

In 1999, Lotus developed the SmartMove program which included bundled tools and services to move users away from host-based and LAN email systems, including cc:Mail and Microsoft Mail, to Lotus Notes Mail and Domino.

Format specifications Explanation of format description terms

Useful references


Last Updated: 08/30/2023