Microsoft Exchange Server provides applications called rule providers that have access to rules through MAPI folder properties. The set of rules for a user is maintained on a folder in the information store and is exposed through the MAPI property PR_RULES_TABLE (read-only), and the MAPI property PR_RULES_DATA (writable). PR_RULES_TABLE can be read using an IMAPITable interface, and PR_RULES_DATA can be read and edited through the IExchangeModifyTable interface. These properties and interfaces are defined in the EDKMDB.H file.
Besides the IExchangeModifyTable interface, a number of functions exist that can be used to add rows to the rule table, delete rows from the table, and enumerate the contents of the table. These individual functions may be easier to use for certain limited applications. See Creating a Rule.