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  MS Outlook to Unix Mailbox Conversion mini HOWTO
  Greg Lindahl,
  v1.4, 2004-01-08

  This MiniHowto covers conversion of old email in Microsoft Outlook
  (not Outlook Express!) to typical Unix file formats.

  Table of Contents

  1. Introduction

     1.1 Copyright
     1.2 Disclaimer
     1.3 News
     1.4 Other ways of doing this

  2. Converting using Mozilla Mail

  3. Converting using IMAP

     3.1 Preparation
     3.2 Install an IMAP server (temporarily!) on your Linux box
     3.3 Connect your Outlook client to the server
     3.4 Copy over all your email
     3.5 Deinstall IMAP from your Linux box


  1.  Introduction

  While several programs exist to convert some formats such as Microsoft
  Outlook Express to Unix formats, Outlook users have a bit more of a
  challenge. One way to convert uses Mozilla Mail under Windows; another
  involves a more complicated method. Both are explained in this

  The database format that Outlook uses for .PST files, called Jet, is
  documented at:

  1.1.  Copyright

  Copyright (c) 2001-2004 by Greg Lindahl

  Permission is granted to copy, distribute and/or modify this document
  under the terms of the GNU Free Documentation License, Version 1.1 or
  any later version published by the Free Software Foundation; with no
  Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
  Texts. A copy of the license may be found at:

  I request that corrections and/or comments be forwarded to the
  document maintainer. If you're considering making a derived work other
  than a translation, I request that you discuss your plans with the
  current maintainer.

  1.2.  Disclaimer

  Use the information in this document at your own risk. I disavow any
  potential liability for the contents of this document. Use of the
  concepts, examples, and/or other content of this document is entirely
  at your own risk.

  All copyrights are owned by their owners, unless specifically noted
  otherwise.  Use of a term in this document should not be regarded as
  affecting the validity of any trademark or service mark.

  Naming of particular products or brands should not be seen as

  You are strongly recommended to take a backup of your system before
  major installations, and backup your system at regular intervals.

  Do not place your cat in a running microwave oven.

  1.3.  News

  1.01: Fixed minor typo in inetd/xinetd startup instructions.

  1.1: Added information about Kmailcvt, Mozilla, and how to get Outlook
  to talk to IMAP servers if it's in Exchange mode.

  1.2: Added details about using Mozilla to do this same task

  1.2.1: Fixed formatting typo.

  1.2.2: Relicensed under the GFDL, more minor typo fixes.

  1.3: Yet more minor fixes.

  1.4: Information about TNEF stuff from Scott Phelps (thanks!)

  1.4.  Other ways of doing this

  A list of conversion utilities, many commercial, may be found at:

  I've had a claim that the program Kmailcvt now converts Outlook
  mailboxes. However, I'm not 100% sure that this claim is true, since
  Kmailcvt definitely converts Outlook Express mailboxes, which are
  completely different from Outlook mailboxes. So, if you figure this
  out, please let me know.

  2.  Converting using Mozilla Mail

  I've also heard that Mozilla Mail under Windows can convert Outlook
  mailboxes -- but the only solid report I've gotten was that
  attachments were not converted, so if they matter to you, don't use
  this method.

  There is some documentation on the Ximian Evolution website. I haven't
  tried this since I don't have a Windows machine anymore. But, here's
  what they say to do:

  Run Mozilla Mail

  Go to "File > Import" and select that you wish to import mail from
  Outlook. When that's done, you're almost there.

  I believe that Mozilla stores all its mailboxes as Unix mbox format
  files, even under Windows. So, all you have to do is transfer those
  files to your Linux box. You can find them in:

  Data/Mozilla/Profiles/default/XXX/Mail/imported.mail/, where XXX will
  be some collection of digits. If there are multiple users on your
  Windows machine, "default" will instead be your username.

  As I mentioned earlier, I've never tried this method, so I don't know
  how well it works. In particular, the issues raised in section 3.4
  probably also apply to this method of conversion.

  By the way, the reason that Mozilla can only read Outlook mailboxes
  under Windows is because it calls a Microsoft DLL to do it.

  3.  Converting using IMAP

  3.1.  Preparation

  First, be sure you want to do things this way. In particular, section
  2 explains how to use Netscape Mail under Windows to do the coversion.
  That's easier than doing it this way.

  If you decide to do it this way, you need to make sure that your copy
  of Outlook can talk to IMAP servers. When I first wrote this HOWTO, I
  assumed that Outlook was Outlook was Outlook. Nope. If you are using
  Outlook in Corporate/Workgroups mode (which talks to Exchange) instead
  of Internet Mode (which talks to POP/IMAP servers), you'll have to
  change modes.

  To test to see if you're OK, look at the Outlook "Tools" menu, and see
  if there is an "Accounts" item. If there is, you're OK, and you can go
  on to section 3.2. If there isn't, go find your towel, and keep

  Changing modes is not trivial, but a helpful reader (Matt Huyck) sent
  in the following instructions, which look dangerous, and which I have
  not tested:

  Select "Options..." from the "Tools" menu, and then go to the "Mail
  Services" tab in the resulting Options dialog box.  At the bottom of
  that tab there is a button labeled "Reconfigure Mail Support..." Hold
  your breath and then click it.  A new window comes up with "Outlook
  2000 Startup" in the title bar and an "E-mail Service Options"
  heading.  There are two relevant radio buttons: "Internet Only" and
  "Corporate or Workgroup".  Change over to "Internet Only" and click
  "Next >".  You are then prompted with a very long message box which
  you should read carefully because you're about to make a significant
  (but reversible) change to the Exchange client configuration.  If you
  haven't passed out already, you can stop holding your breath now.
  Although it doesn't explicitly say so, you will want to be sure you
  have a copy of the Microsoft Office install CD before you click "Yes".
  Click "Yes" and let Outlook do its thing for a few seconds until it
  has quit completely.  Open up Outlook again.  This is where you may be
  prompted for the install CD.  After the re-configuration is complete
  you're ready to proceed with step 3.2 of the HOWTO.

  To get back to your original Outlook configuration, follow the same
  directions, but you'll obviously be clicking the *other* radio button.

  One other thing is different if you've been using Exchange.  As you
  point out at the end of section 3.4,  "the original 'From ' line" is
  not preserved.  For Exchange users, however, the comment "Fortunately
  you don't actually need that information" doesn't quite apply.  The
  "From" header that's missing is the only one that contains the
  identity of the sender in messages that were sent on an internal
  Exchange server, i.e. messages that didn't pass through an Internet
  gateway anywhere.  I have preserved my "From" headers by saving copies
  of my mail folders as text files through the "Import and Export..."
  command from the "File" menu.  I plan to hack out some twisted
  Perl/Grep code that will re-insert those "From" headers into my Linux
  mbox files.  If I get that to work I'll let you know.

  3.2.  Install an IMAP server (temporarily!) on your Linux box

  Installing things varies from Linux distribution to distribution, so I
  will use RedHat 7.0 as an example.  First you need to install the
  correct package, which generally is named "imap". or "uw-imap" or
  something like that:

        cd /home/redhat-7.0-cd/RedHat/RPMS
        ls *imap*
        rpm -i imap*

  Actually, since I had a "workstation" install, I also had to install
  the xinetd package; rpm gave me an error which told me to do this.
  And, of course, it was on the second CD of RedHat 7.0. Debian users
  using "apt-get" don't have to worry about such issues.

  Next, we need to enable the imap server. On my Gnome-basekd desktop
  this is done using the graphical tool at Start -> System Settings ->
  Server Settings -> Services, or you can do it by hand. This is usually
  controlled by a line in the file /etc/inetd.conf:

        #imap    stream  tcp     nowait  root    /usr/sbin/tcpd        /usr/sbin/imapd

  The above line is commented out; remove the leading # sign.
  Alternately, if your system uses xinetd, instead edit
  /etc/xinetd.d/imap and change "disable=yes" to "disable=no".

  Then restart inetd or xinetd by doing:

        /etc/rc.d/init.d/inetd restart


   /etc/rc.d/init.d/xinetd restart

  If all else fails, reboot.

  You don't actually want to leave the IMAP server enabled for that
  long. This server runs as root and has had security bugs in the past.
  For this reason, you shouldn't leave it enabled unless you wish to use
  it permanently. We will disable this server in section 3.5.

  In order to connect Outlook to this IMAP server, you will need to know
  the name or IP address of the Linux box.

  3.3.  Connect your Outlook client to the server

  In order to copy over all our email to the server, we need to tell
  your Outlook client about this new server. Select "Accounts..." from
  the "Tools" menu, and then "Add" a new account "Mail...". The
  important items are that the server uses IMAP to download email, that
  the incoming mail server is the name or IP address of your Linux box
  from section 3.2, and the username and password should be your
  username and password on the Linux box. (As usual, it's a bad idea to
  use the root account on Linux for this purpose.)

  Once you've hit "Finish", set this new account to be the default by
  highlighting it and clicking on "Set as Default". Outlook should
  connect to your IMAP server, and the name of your IMAP server should
  appear at the bottom of your folder list. Click on it; you should see
  an Inbox folder. (Note that if /var/mail/yourusername doesn't exist on
  your Linux box, you won't be able to drag-and-drop any messages into
  your INBOX... and the error message will be confusing. However, that's
  not what we're going to do.)

  3.4.  Copy over all your email

  At this point you can drag and drop entire folders of email from
  Outlook onto the IMAP server name. This will copy the email, including
  all attachments, to the Linux box. Unfortunately it also immediately
  deletes it from Outlook. In order to copy items without deleting them,
  right-click on the folder name and select the "Copy" option. For the
  destination, pick your Linux server at the bottom of the list.

  However, life isn't quite that simple. Outlook supports folders
  containing folders which also contain messages. Linux IMAP servers do
  not support that (at least those using Mailbox format); a folder is
  either a regular file containing messages, or a directory containing
  subdirectories and files. So if you have folders in Outlook with both
  messages and subfolders, you can't copy the entire tree over to the
  Linux IMAP server. Another incompatibility of the Linux IMAP server is
  that you have to tell it in advance if a new folder will contain
  subfolders or messages. You do this by appending a slash (/) to the
  folder name when you create it. This slash will disappear when the
  folder is created.

  So, in order to copy a tree of folders to the Linux IMAP server, first
  you need to create a replica of the structure of your existing folders
  on the Linux IMAP server. While you're doing this, note which of the
  existing folders contain both subfolders and messages. You will need
  to move these messages elsewhere. Once you have the overall tree
  created, then you can copy or move groups of folders to the Linux IMAP

  One final incompatibility to note is that the Linux IMAP server
  doesn't allow folders with slashes (/) in their name. You'll need to
  rename such folders before copying or moving them.

  On the Linux box, folders appear as files and directories in your home
  directory. The format of these files is the usual Unix mail format,
  which most Unix/Linux mail tools either use directly or can convert
  to/from. Files with attachments will have MIME attachments; there is
  also one extra message per folder which is a (useless) header.

  (One piece of data which doesn't get preserved is the original "From "
  line, which contains the envelope address of the email. Fortunately
  you don't actually need that information.)

  An additional wrinkle applies regarding attachments. Microsoft
  sometimes bundles together several attachments into a ms-tnef
  attachment; TNEF stands for Transport Neutral Encapsulation Format.
  This attachment contains several mime-encoded attachments.  I was
  lucky that my mail folders didn't contain any of these -- they seem to
  be created when people send you "Rich Text Format" email -- it
  contains two alternatives, one in plain text and the other a TNEF-
  encapsulated version of the message in rich text plus any attachments.

  Fortunately, there are some ways to unpack TNEF attachments.  One is
  the tnef project hosted on sourceforge, the other is ktnef, which is a
  part of KDE.

  3.5.  Deinstall IMAP from your Linux box

  Once you've transferred all of your email, you will want to deinstall
  the IMAP server from your Linux box, for the security reasons
  mentioned earlier. This involves the same 2 steps you took to install
  the server:

  1. Remove the RPMs:

         rpm -e imap

  2. Remove the line in /etc/inetd.conf or /etc/xinetd.d/imap

  3. Restart inetd or xinetd, or reboot.

  Voila! You have taken another step towards a Microsoft-free lifestyle.

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