MAPI is an abbreviation for Messaging Application Programming Interface, an application programming interface, that allows other applications to access news items (e.g. e-mails).Many Document Management Systems use MAPI to archive e-mails or to send a document via e-mail.
MAPI is generally understood to be Microsoft's messaging API, which is already supplied with MS-Windows. Some additional products of the same manufacturer, like MS-Exchange and MS-Outlook extend MAPI with additional capabilities. The functions of MAPI are usually contained in the computer in the file mapi.dll. Other manufacturers, which offer software in the messaging area, also implement their own MAPI function collections. Often several different versions of mapi.dll are found on the same computer, which can lead to software incompatibilities and associated malfunctions.
The MAPI offers possibilities to send automated e-mail and is a danger moment, because malicious software can use MAPI to send SPAM messages for example. Therefore, Microsoft has in the meantime repeatedly worked on the security of the MAPI function collection. Unfortunately this led in the past to clear comfort losses with the users, because often MAPI operations had to be confirmed again and again by the user. In the meantime, however, viruses and Trojans use other methods for SPAMming and MAPI has again moved somewhat out of the focus of security experts.