========================
|| INSTALLING IMP 4.0 ||
========================

This document contains instructions for installing the IMP web-based
mail client on your system.

For information on the capabilities and features of IMP, see
the file README in the top-level directory of the IMP
distribution.


OBTAINING IMP
-------------

IMP can be obtained from the Horde website and FTP server, at

   http://www.horde.org/imp/
   ftp://ftp.horde.org/pub/imp/

Bleeding-edge development versions of IMP are available via CVS; see
the file docs/HACKING in the Horde distribution for information on
accessing the Horde CVS repository.

While previous versions of IMP were numbered to correspond with a
particular version of the Horde Framework, that is no longer true as
of IMP version 3.0. The current version of Horde will work with the
current version of Horde applications.

[FIXME note on RPMs here]


PREREQUISITES
-------------

To function properly, IMP REQUIRES the following:

  1. A working Horde installation.

     IMP runs within the Horde Application Framework, a set of
     common tools for Web applications written in PHP. You must
     install Horde before installing IMP.

     The Horde Framework can be obtained from the Horde website and
     FTP server, at

        http://www.horde.org/horde/
        ftp://ftp.horde.org/pub/horde/

     Many of IMP's prerequisites are also Horde prerequisites.
     Be sure to have completed all of the steps in the INSTALL
     file for the Horde Framework before installing IMP.

  2. The following PHP capabilities:

     a. IMAP and POP3 support (--with-imap)

        PHP uses the UW-IMAP c-client library to provide IMAP and
        POP3 support. C-client is available from

           ftp://ftp.cac.washington.edu/imap/

        IMP REQUIRES IMAP and POP3 support in PHP, and can use
        IMAP-SSL and POP3-SSL if available.

        IMPORTANT NOTE: c-client support is broken in PHP 4.2.2 & 4.2.3.
        If you are using either of these versions you can not use any
        'imap-2002' releases or else IMP will not function properly. If this
        is your situation, you have 2 options:

          1. If using PHP 4.2.3, you can apply this patch:
          http://lists.horde.org/archives/imp/Week-of-Mon-20021111/026936.html

          2. Downgrade to using the 'imap-2001a' source code.

     b. File Upload Support

        File upload support is REQUIRED to allow attachments in mail
        composition and to allow various importing features to work (e.g.
        importing PGP or S/MIME keys, importing mbox files).  To enable file
        upload support:

            1. In your php.ini file, the following line must be present:
               file_uploads = On

            2. Your temporary upload directory must be writable to the
               user the web server is running as. If you leave the
               configuration option 'upload_tmp_dir' blank in php.ini, PHP
               will use its' default directory (normally /tmp).

            3. Set the maximum size of the uploaded files via the
               'upload_max_filesize' configuration option in php.ini.  For
               example, to allow 5 MB attachments, place the following line
               in your php.ini file:
               upload_max_filesize = 5M

         If either file_uploads is turned off, or your temporary upload
         directory is NOT writable by the server, these options
         will be disabled and will not be available to the user.

  3. At least one IMAP or POP3 server.

     While IMP is an application that is installed on a Web server
     and is run from a Web browser, it is only an IMAP and POP3
     *client*, like Eudora or Outlook Express. You must have access
     to an IMAP or POP3 server (or multiple servers) on which your
     users' mail is stored in order to use IMP.

     IMAP is recommended over POP3 in order to let users maintain
     mail folders other than INBOX. IMAP is also _much_ faster than POP3
     in displaying a mailbox of messages.

The following are not required, but are strongly RECOMMENDED:

  1. Sendmail or equivalent.

     While Horde can inject mail via either a local sendmail or
     a remote SMTP server, the former is recommended for use with
     IMP for improved performance and error handling as well as
     a more accurate envelope.

  2. Turba, the Horde contacts manager.

     Turba is the Horde contact management application, designed to be
     integrated with other Horde applications to provide a unified
     interface to contact management throughout the Horde suite.
     Turba is available from:

        http://www.horde.org/turba/
        ftp://ftp.horde.org/pub/turba/

     Turba provides a local address book and an LDAP directory
     search function to IMP.

  3. Ingo, the Horde mail filters manager.

     Ingo is the Horde mail filters management application, designed to be
     integrated with other Horde applications to provide a unified
     interface to filter management throughout the Horde suite.
     Turba is available from:

        http://www.horde.org/ingo/
        ftp://ftp.horde.org/pub/ingo/

     Ingo provides the mail filtering interfaces to IMP.
     You must use the 2.x branch of Ingo with IMP 4.x.

     To use IMAP client-side filtering (i.e. the filtering provided by
     IMP 3.x), ingo should use the 'null' driver and the 'imap' script
     settings (set in ingo/config/backends.php).

  4. Ispell, or a drop-in replacement.

     Ispell, or its enhanced cousin aspell, is used as IMP's
     spell-checking engine. You must install one of these, or
     a similar program with an ispell-compatible interface, to
     use IMP's spell-check feature.

     The differences between ispell and aspell are subtle but
     important. The author of ispell writes:

  [Aspell's] primary advantage is that it is better at making
  suggestions when a word is seriously misspelled. For example, when
  given "trubble", ispell will suggest only "rubble", where aspell
  suggests "trouble" (as its first choice) as well as "dribble",
  "rubble", and a lot of other words. Its disadvantage is that the
  approximate-matching algorithm is specific to English.

     As IMP supports multiple languages, the languages required
     by your user base will probably provide an incentive to use
     one or the other. You can obtain International Ispell from

        http://fmg-www.cs.ucla.edu/fmg-members/geoff/ispell.html

     and aspell from

        http://aspell.sourceforge.com/


INSTALLING IMP
--------------

IMP is written in PHP, and must be installed in a web-accessible
directory. The precise location of this directory will differ from
system to system. Conventionally, IMP is installed directly underneath
Horde in the web server's document tree.

Since IMP is written in PHP, there is no compilation necessary;
simply expand the distribution where you want it to reside and rename
the root directory of the distribution to whatever you wish to appear
in the URL. For example, with the Apache web server's default document
root of '/usr/local/apache/htdocs', you would type:

   cd /usr/local/apache/htdocs/horde
   tar zxvf /path/to/imp-4.0.tar.gz
   mv imp-4.0 imp

and would then find IMP at the URL

   http://your-server/horde/imp/


CONFIGURING IMP
---------------

1. Configuring Horde for IMP

   a. Register the application

      In horde/config/registry.php, find the applications['imp'] stanza.
      The 'status' parameter should already be marked '=> 'active''.
      If you have changed the location of IMP relative to Horde,
      either in the URL or in the file system or both, you must
      update the 'fileroot' and 'webroot' settings to their correct
      values.

   b. Optional: Enable IMP authentication

      If you would prefer that your users authenticate directly with IMP,
      without having to authenticate through Horde first, uncomment the
      following Horde auth driver lines in horde/config/horde.php:

         $conf['auth']['driver'] = 'application';
         $conf['auth']['params']['app'] = 'imp';

      ** YOU WILL HAVE TO LOG IN TWICE IF YOU DON'T DO THIS -- Once
         to Horde and a second time to IMP.

      ** If this is a new install, you will not be able to configure
         IMP using the Horde Administration/Configuration tool if you
         first enabled IMP authentication for Horde. You must set Horde
         to use another authentication method, configure IMP, then reset
         Horde to use IMP authentication.

2. Configuring IMP.

   To configure IMP, change to the config/ directory of the
   installed distribution, and make copies of all of the configuration
   "dist" files without the "dist" suffix:

      cd config/
      for foo in *.dist; do cp $foo `basename $foo .dist`; done

   Documentation on the format and purpose of those files can be found in
   each file.   You may edit these files if you wish to customize IMP's
   appearance and behavior.  With two exceptions (conf.php and servers.php)
   the defaults will be correct for most sites.

   You must be sure to list your IMAP/POP3 server names and configuration
   information in servers.php (unless you demand that the user specify his
   own at login).

   You must then login to Horde as a Horde Administrator to finish the
   configuration of IMP.  Use the Horde "Administration" menu item to get
   the the Administration page, and then on the click on the "Configuration"
   icon to get the Configuration page.  Select "Mail" from the selection
   list of applications, and click on the "Configure" button.  Fill in or
   change any configuration values as needed.  When done click on "Generate
   Mail Configuration" to generate the conf.php file.  If your web server
   doesn't have write permissions to the IMP configuration directory or
   file, it will not be able to write the file.  In this case, cut and
   paste the returned configuration information into the file
   imp/config/conf.php.

   Note for international users:  IMP uses GNU gettext to provide local
   translations of text displayed by applications; the translations are
   found in the po/ directory.  If a translation is not yet available
   for your locale (and you wish to create one), or if you're having
   trouble using a provided translation, please see the
   horde/docs/TRANSLATIONS file for instructions.

3. Securing IMP

   Before you can secure IMP, you need a secure Horde installation.
   Please read the file in horde/docs/SECURITY for Horde security
   information before proceeding.

   There are two channels by which, unless steps are taken to avoid
   it, IMP encourages users to pass their IMAP and POP3 passwords
   around the Internet unencrypted.

   The first channel is between their browser and the Web server.
   We strongly recommend using an SSL-capable Web server to give
   users the option of encrypting communications between their
   browser and the Web server on which IMP is running; some sites
   may wish to disable non-SSL access entirely.

   The second channel is between the Web server and their IMAP
   or POP3 server. The simplest way to avoid this is to have the
   mail server running on the same system as the Web server, and
   configuring IMP to connect to the IMAP or POP3 server on
   "localhost" instead of on the Internet hostname. In cases where
   that is not possible, we recommend using IMAP-SSL or POP3-SSL to
   ensure that users' passwords remain safe after they have entrusted
   them to IMP.

   Other security steps you can take to increase security include:

   * Use session cookies instead or URL based sessions.
   * Set your php session.entropy_length to a larger value (e.g. 16)
     and session.entropy_file to a random source (e.g. /dev/urandom)
   * Enable and use the php mycrypt extension.
   * If your database, mail server, and web server are on the same host
     machine, then:
       * use unix socket database access and disable tcp database access.
       * use 'localhost' for all tcp/ip connections to avoid the network.
       * use the command-line sendmail for sending mail if possible.

4. Testing IMP

   Use IMP to login to a known working IMAP or POP3 server. Test at
   least the following:

     - Sending mail (via the "Compose" item in the menu bar).
     - Setting preferences (check to see if they survive after logging
       out and back in, if you are using an SQL or LDAP preferences
       system).
     - Reading mail.
     - Changing folders.


OBTAINING SUPPORT
-----------------

If you encounter problems with IMP, help is available!

The Horde Frequently Asked Questions List (FAQ), available on the Web
at

  http://www.horde.org/faq/

The Horde Project runs a number of mailing lists, for individual
applications and for issues relating to the project as a whole.
Information, archives, and subscription information can be found at

  http://www.horde.org/mail/

Lastly, Horde developers, contributors and users also make occasional
appearances on IRC, on the channel #horde on the Freenode Network
(irc.freenode.net).

Please keep in mind that IMP is free software written by volunteers.
For information on reasonable support expectations, please read

  http://www.horde.org/support.php

Thanks for using IMP!

The IMP team
imp@lists.horde.org

$Horde: imp/docs/INSTALL,v 1.39 2003/06/11 03:03:10 ericr Exp $
