Topic Last Modified: 2007-01-23

The Microsoft® Exchange Database Troubleshooter Tool detected one or more MSExchangeIS 9519 events with error code 0xfffffb3a in the Application log. This error indicates that another copy of the same database is already running.


Each Exchange database has its own unique signature. If the Microsoft Exchange Information Store service detects multiple databases with the same signature, it will prevent the duplicate database from mounting.

The event can also be identified as error -1222, JET_errDatabaseSignInUse.

User Action

You can verify that two copies of the same database are present within a single storage group by following these steps:

  1. Dismount all other databases in the storage group, and try to mount the database that caused this error message.

  2. If the database is able to mount, you must then try to mount all the other databases in the storage group.

  3. If a different database in the storage group now gives the same error in the Application log, then two databases have the same signature; therefore, they are copies of the same database.

To resolve this issue, make sure that only one copy of the database is present within this particular storage group.