The following reasons could result in a corrupted or missing database index:

• This can occur during index cleanup of an Exchange database after you apply a new Microsoft Windows service pack. After you apply the service pack, you cannot mount the mailbox or the public folder databases in the Exchange server. Additionally, events ESE 609 and ESE 611 are logged in the Application event log.
  
  
• This can occur after you run a database repair operation (eseutil /p). This can remove an index that is generated when the database is first created. Running the Eseutil repair command removes the index.
  
  

This error can also be identified as -1404, JET_errIndexNotFound. This error applies to the following versions of Exchange server:

• Microsoft Exchange Server 2007
  
  
• Microsoft Exchange Server 2003
  
  
• Microsoft Exchange 2000 Server
  
  

To resolve this issue, follow the resolution that matches the problem scenario described earlier:

• If an index is corrupted during index cleanup of an Exchange database after you apply a new Windows service pack, follow these steps:
  
  
  1. Restore the affected mailbox or public folder database from a known good backup.
     
     
  2. Perform an offline defragmentation of the affected database by running eseutil /d. For information about how to defragment the affected database offline, see the following topics:
     
     Exchange 2000 Server and Exchange Server 2003 databases: How to Run Eseutil /D (Defragmentation)
     
     Exchange Server 2007 databases: How to Run Eseutil /D (Defragmentation)
     
     
• If an index is missing after you run a database repair (eseutil /p) operation, apply the hotfix prescribed in Microsoft Knowledge Base article 924627, Event ID 9519 that includes error 0xfffffa84 is logged when you try to mount a database after you use the Eseutil and Isinteg utilities to recover the database in Exchange 2003.