One object that is included in a second object. An object embedded in a Microsoft Exchange Server message and represented as an icon is called an attachment.
event log
A file that records any significant occurrences in the system or in an application.
extension data
Data with fields other than the standard configuration data provided by the Microsoft Exchange Server Administrator program that are stored by a directory object. One extension-data attribute can contain a number of extension-data fields of varying data types. Extension data is commonly used when an application must expose information that is outside the application's schema.
EX
The address type for native Microsoft Exchange Server addresses.