Outlook Express uses the Windows Address Book to store contact information and integrates tightly with it.

[2] This add-on precedes the Internet Mail profile for Microsoft Exchange 4.0 bundled in Windows 95.

In 1997 the program was changed and renamed to Outlook Express and bundled with Internet Explorer 4.

The Windows executable file for Outlook Express, msimn.exe, is a holdover from the Internet Mail and News era.

Internet Explorer 5 required Outlook Express 5 to save Web Archive files (see MHTML).

[7] Beginning with the text-based Unix Mail command, email traditionally used the inline or bottom posting styles when replying to messages.

This has led to a thriving market for software that can back up, restore and recover corrupted files.

[9] An open-source project called UnDBX was also created, which seems to be successful in recovering corrupt databases.

[10] 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.

With Outlook Express SP2 (part of Windows XP SP2), Microsoft has tried to correct the security holes.

[16] Outlook Express does not correctly handle MIME,[17] and will not display the body of signed messages inline.

Programmatic access to, or control of Outlook Express for custom messaging applications or plugins is not officially documented or supported by Microsoft.