The BlackBerry state database was introduced in BlackBerry Enterprise Server version 2.0 SP2. The database is given a random number (for example, 12345678.nsf) and is located under the Lotus Domino Data directory, BES\State\ folder on the BlackBerry Enterprise Server.

A state database is created for each BlackBerry smartphone user, and it is a repository used by the BlackBerry Enterprise Server to store information about messages sent to and from the BlackBerry smartphone. The information stored in the database supports most functionalities, such as reply-with-text, message forwarding, message filing, and email reconciliation.

The status of filtered messages is also kept in this database to prevent re-processing of the messages. The initial database is just under 200 KB, and as documents are added to the BlackBerry state database, it grows by less than 100 bytes per document, although heavy mail users' databases may grow to be a few MB in size.

When a BlackBerry smartphone user is removed from the Blackberry Enterprise Server, this removes the link between the BlackBerry smartphone user’s BlackBerry profiles database document and the BlackBerry state database. This will orphan any messages that are currently on the BlackBerry smartphone, if the BlackBerry smartphone user is re-added to the Blackberry Enterprise Server. A warning is displayed that must be confirmed before the action is allowed.

The BlackBerry state database also enables mobile IBM Lotus Notes clients the ability to use the BlackBerry Desktop Manager for email reconciliation with a local replica (even while disconnected). This works if you have a local replica of both your mail file and your BlackBerry state database.