Outlook Express was an
e-mail/
news client that was 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 XP, and was available for
Windows 95 and
Mac OS 9. In
Windows Vista, Outlook Express is replaced with
Windows Mail.
Windows Live Mail has since been released as the successor to Outlook Express and Windows Mail.
Microsoft Entourage, sold as part of
Microsoft Office for
Macintosh, has replaced the Macintosh version.
Outlook Express is a different application from
Microsoft Office Outlook. The two programs do not share a common codebase, but do share a common architectural philosophy. The similar names lead many people to incorrectly conclude that Outlook Express is a stripped-down version of
Microsoft Office 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 was a
freeware e-mail 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 (
RTF) e-mail, lacking
HTML e-mail.
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 Office Outlook.
Internet Explorer 5 required Outlook Express 5 to save Web Archive files (see
MHTML).
Outlook Express 6 SP3 is the latest version which is part of Windows XP SP3. Extended support for Windows XP SP3, which covers security hotfixes, will end in 2014.
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 . Microsoft was also concurrently developing Windows Live Mail Desktop (later renamed to
Windows Live Mail), a mail client for its
Hotmail service. Windows Live Mail was released in November 2007. In the future, support for Outlook Express and Windows Mail will be discontinued in favor of Windows Live Mail.
Versions for Windows
- Outlook Express 4.0, which was included in Windows 98 (June 1998), stored messages in *.mbx files (similar to the Mbox format used in Unix based systems).
- Outlook Express 5.0, which was included in Windows 98 Second Edition (SE) (June 1999), switched to *.dbx files, with a separate file for each mailbox folder.
- Outlook Express 5.0 was included in Windows 2000 (February 2000).
- Outlook Express 5.5 was included in Windows Me (June 2000).
- Outlook Express 6.0 was included in Windows XP (October 2001).
- Outlook Express 6.0 SP2 was included in Windows XP Service Pack 2 (August 2004).
- Outlook Express 6.0 SP3 was included in Windows XP Service Pack 3 (April 2008).
Versions for Mac
Criticism
E-mail standards
Beginning with the text-based
Unix Mail command, e-mail traditionally used the inline or bottom
posting styles when replying to messages. Outlook Express, as well as
Lotus Notes and Microsoft Outlook, top-post (show replies newest to oldest) by default. The large installed base of Microsoft Windows and Microsoft Office has changed perceptions of posting style to the point where users have come to expect the top-posting style and are confused by inline or bottom posting.
Microsoft Office Outlook and
Microsoft Exchange use a
proprietary e-mail attachment format called
Transport Neutral Encapsulation Format (TNEF) to handle formatting and other features specific to Outlook such as meeting requests. Outlook Express and other e-mail clients are unable to read this format. This can be confusing to Outlook Express users (as well as those who use other e-mail clients) 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 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. Microsoft has released which may be able to correct problems and restore access to e-mail messages, without resorting to third-party solutions.
However, with 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 e-mail clients to support
HTML e-mail 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 e-mail could cause code to run without the user's knowledge or consent. Outlook Express uses Internet Explorer to render HTML e-mail. Internet Explorer has been widely criticized for having numerous security flaws.
With Outlook Express SP2 (part of Windows XP SP2), Microsoft has tried to correct the security holes. Outlook Express now blocks images inside e-mails by default. It uses only the restricted security zone for HTML e-mail, 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 blank e-mail and two attachments (one of the message text and one of the signature) and therefore need to open an attachment to see the e-mail. If the email has been
forwarded several times, users need to open attached email messages one inside the other multiple times till they reach the parent e-mail message. This bug has still not been rectified. The proper behavior is described in .
Extensibility
Outlook Express does not have a documented
object model like
Microsoft Office 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 (licensed under
GPL). By 2003, some companies provided commercial solutions to develop add-ins. Some popular toolkits are , and
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 (now for US English and numerous other languages) 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. Also, 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.
See also
