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Article ID: 2621266 - Last Review: February 11, 2014 - Revision: 5.0


The Microsoft Exchange Server 2010 mailbox database grows unexpectedly large. The size of the mailbox database is not reduced when items are deleted from mailboxes. 

This issue most frequently occurs when one of the following conditions is true. However, it may also occur in other scenarios: 
  • A journaling mailbox is deployed in the Exchange Server 2010 environment.
  • A third-party email message archival system is used.


This issue can occur because the Microsoft Exchange Information Store service does not reclaim database space when items are deleted.


To resolve this issue, install Exchange Server 2010 Service Pack 3 ( .

For more troubleshooting information, go to the following Microsoft TechNet website:
Troubleshooting Exchange 2007 Store Log/Database growth issues (


To work around this issue, follow these steps:
  1. Create a new mailbox database.
  2. Move the mailboxes to the new mailbox database. 
  3. Delete the old mailbox database.

This workaround recovers the leaked database space. However, the new database may start leaking space. You have to apply the fix to prevent new leaks.


For more information about how to create and configure a journaling mailbox, go to the following TechNet website: (
 For more information about how to configure deleted items retention and recoverable items quotas, go to the following TechNet website: (

Applies to
  • Microsoft Exchange Server 2010 Enterprise
  • Microsoft Exchange Server 2010 Standard
kbqfe kbfix KB2621266
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