Outlook Express is a discontinued email and news client included with Internet
Explorer versions 4.0 through 6.0. As such, it was also bundled with several
versions of Microsoft Windows, from Windows 98 to Windows Server 2003, and
was available for Windows 3.x, Windows NT 3.51, Windows 95 and Mac OS 9. In
Windows Vista, Outlook Express was superseded by Windows Mail, then again
by Windows Live Mail as separate software. Microsoft Entourage and then
Microsoft Outlook, sold as part of Microsoft Office for Macintosh, has
replaced the Macintosh version. Outlook Express is a different
application from Microsoft Outlook. The two programs do not share a common
codebase, but do share a common architectural philosophy. The similar
names lead many people to conclude incorrectly that Outlook Express is a
stripped-down version of Microsoft Outlook. Outlook Express uses the
Windows Address Book to store contact information and integrates tightly with
it. On Windows XP, it also integrates with Windows Messenger.
History Microsoft Internet Mail and News is a
discontinued email and news client and ancestor of Outlook Express. Version 1.0
was released in 1996 following the Internet Explorer 3 release. This add-on
precedes the Internet Mail profile for Microsoft Exchange 4.0 bundled in
Windows 95. Version 2.0 was released at the end of 1996. In 1997 the program was
changed and renamed as Outlook Express and bundled with Internet Explorer 4.
The executable file for Outlook Express, msimn.exe, is a holdover from the
Internet Mail and News era. Internet Mail and News handled only plain text
and rich text email, lacking HTML email. At one point, in a later beta version of
Outlook Express 5, Outlook Express contained a sophisticated and adaptive
spam filtering system; however this feature was removed shortly before
launch. It was speculated on various websites and newsgroups at that time,
that the feature was not stable enough for the mass market. Nearly two years
later, a similar system, using a similar method of adaptive filtering, appeared
as a feature of Microsoft Outlook. Internet Explorer 5 required Outlook
Express 5 to save Web Archive files. Outlook Express 6 is the last version to
get the same name. It has a similar layout to Outlook Express 5. It was
included with Windows XP. In October 2005, Microsoft announced
that Windows Vista would exclusively include a new application named Windows
Mail, based on large parts of Outlook Express source code. In November 2007,
Microsoft released Windows Live Mail, a mail client for its Hotmail service.
= Versions for Windows = Outlook Express 4.0 which was included
in Windows 98, stored messages in *.mbx files
Outlook Express 5.0 which was included in Windows 98 Second Edition, switched
to *.dbx files, with a separate file for each mailbox folder
Outlook Express 5.01 was included in Windows 2000
Outlook Express 5.5 was included in Windows Me
Outlook Express 6.0 was included in Windows XP
= Version for Mac = Outlook Express 4.0 was included in
Microsoft Office 98 Macintosh Edition. Criticism
= Email standards = Beginning with the text-based Unix Mail
command, email traditionally used the inline or bottom posting styles when
replying to messages. Outlook Express, as well as Lotus Notes and Microsoft
Outlook, top-post by default. Microsoft Outlook and Microsoft Exchange
use a proprietary email attachment format called Transport Neutral
Encapsulation Format to handle formatting and other features specific
to Outlook such as meeting requests. Outlook Express and other email clients
are unable to read this format. This can be confusing to Outlook Express users
who receive attachments sent from Outlook.
= Database corruption = Outlook Express has been prone to a
number of problems which can corrupt its files database, especially when the
database increases in size due to an increasing number of stored emails and
during database compaction. This has led to a thriving market for programs that
can back up, restore and recover corrupted files. An open-source project
called UnDBX was also created, which seems to be successful in recovering
corrupt databases. Microsoft has also released documentation which may be able
to correct some non-severe problems and restore access to email messages,
without resorting to third-party solutions.
However, with the latest updates applied, Outlook Express now makes
backup copies of DBX files prior to compaction. They are stored in the
Recycle Bin. If an error occurs during compaction and messages are lost, the
DBX files can be copied from the recycle bin.
= Security issues = Outlook Express was one of the earlier
email clients to support HTML email and scripts. As a result, emails were
commonly infected with viruses. Previously, another security flaw was
that a script could automatically be opened as an attachment. Another bug was
in Outlook Express's attachment handling that allowed an executable to appear to
be a harmless attachment such as a graphics file. Opening or previewing the
email could cause code to run without the user's knowledge or consent. Outlook
Express uses Internet Explorer to render HTML email. Internet Explorer has been
widely criticized for having numerous security flaws.
With Outlook Express SP2, Microsoft has tried to correct the security holes.
Outlook Express now blocks images inside emails by default. It uses only the
restricted security zone for HTML email, which disables scripts and imposes
restrictions on what web content can be rendered. It also warns when opening
potentially malicious attachments. = Handling of PGP/MIME signed messages =
Outlook Express does not correctly handle MIME, and will not display the
body of signed messages inline. Users get a filled email and one attachment
and therefore need to open an attachment to see the email. If the email has been
forwarded several times, users need to open attached email messages one inside
the other multiple times to reach the parent email message. This bug has still
not been rectified. The proper behavior is described in RFC1847. When replying
or forwarding a message to a user who has a digital signature, Outlook Express
gives an error and does not allow the user to continue if there is no digital
signature installed for the sender. = Extensibility =
Outlook Express does not have a documented object model like Microsoft
Outlook. Programmatic access to, or control of Outlook Express for custom
messaging applications or plugins is not officially documented and supported by
Microsoft. IStoreNamespace and IStoreFolder interfaces were documented
in 2003, but they are only related to the storage.
Some companies have managed to create their plugins hacking the interface
using Windows hooks. A significant one was the PGP plugin because it was the
only example of a working plugin whose source code was available. By 2003, some
companies provided commercial solutions to develop add-ins.
= Office 2007 spell checker incompatibility =
Outlook Express does not have a dedicated spell checker. It can use the
spell checkers from Microsoft Office if Office is also installed. However, the
Office 2007 spell checkers, except for the French spell checker, are
incompatible with Outlook Express. Microsoft has acknowledged this problem,
but does not provide any sort of remedy. A solution is to install any pre-Office
2007 proofing tools or use a third party spell checking program for Outlook
Express. Windows Live Mail, which is based on Outlook Express's source code,
contains built-in spell checking support and is freely downloadable for Windows
XP. = Glitches and other unusual aspects =
Cancelling sending an email while it is being sent does not effectively prevent
it from being sent. Similarly, when importing .PST files, cancelling the
import while it is in progress merely cancels the import of the current folder
and the import resumes with the next folder. Furthermore, Outlook Express
only supports .dbx files that are smaller than 2 GB, and may have
performance issues when dealing with files approaching that limit.
See also List of Usenet newsreaders
Comparison of Usenet newsreaders References
External links "https:support.microsoft.comkb/257824".
Support. Microsoft. Outlook Express on WebDeveloperNotes.com
Yabo, Pablo. "Reading and Writing Messages in Outlook Express". Code
Project. Outlook Express dbx file format by Arne
Schloh – a partial documentation of the DBX file format with sample code
Outlook Express 5.0 file format – another reverse-engineered .dbx document
with sample code Outlook Express Video Setup – Kurulum –
Outlook Express Video Setup – Kurulum Outlook 2003 Setup – Kurulum – Outlook
2003 Video Setup UnDBX – an open-source tool to extract,
recover and undelete email messages from Outlook Express DBX files