Exchange 2010 RTM introduced store limits to prevent a single application or single user from using all the available connections to the Microsoft Exchange Information Store. In Exchange 2010 SP1, for any connections by users with administrative privileges, the session limits have been increased to 64,000 maximum sessions per server.

For more information, see Exchange Store Limits.

The following describes new functionality related to mailbox databases in Exchange 2010 SP1:

• Mailbox Database Repair Requests   In Exchange 2010 RTM and earlier, you could repair a mailbox with the Information Store Integrity Checker (Isinteg.exe) tool. To repair mailboxes, you needed to dismount the mailbox database on which that mailbox resided and run the fixes while the database was offline. Exchange 2010 SP1 introduces the New-MailboxRepairRequest cmdlet that allows you to detect and repair a corrupted mailbox while leaving the mailbox database online.
  
  For more information, see the following topics:
  
  
  • Managing Repair Requests
    
    
  • New-MailboxRepairRequest
    
    
• Database Log Growth Troubleshooter   The Database Log Growth Troubleshooter script (Troubleshoot-DatabaseSpace.ps1) detects and takes action on excessive log growth that can cause the health of the Mailbox server to be at risk. By default, the configurable troubleshooter runs every 15 minutes to determine the amount of space available on the hard drive. If the hard drive space is less than 25 percent, the troubleshooter runs an algorithm to determine if the problem is caused by excessive log growth. If excessive log growth is the problem, the troubleshooter quarantines or throttles the mailboxes that are causing the excessive log growth. For more information, see Manage Database Log Growth by Using the Troubleshoot-DatabaseSpace.ps1 Script in the Shell.
  
  
• Database Latency Troubleshooter   The Database Latency Troubleshooter script (Troubleshoot-DatabaseLatency.ps1) detects and takes action on high latencies on a database. For more information, see Manage Database Latencies by Using the Troubleshoot-DatabaseLatency.ps1 Script in the Shell.
  
  

The new Remove-StoreMailbox cmdlet allows you to permanently remove soft-deleted and disconnected mailboxes.

The following changes were made to public folders and public folder databases in Exchange 2010 SP1:

• The AggregatePFData.ps1 script now aggregates statistics across all public folder replicas. For more information, see View Public Folder Item Statistics.
  
  
• You can now use the Exchange Management Console to configure client permissions for public folders. For more information, see Use the Public Folder Management Console to Manage Public Folder Settings.
  
  
• The New-PublicFolderDatabaseRepairRequest cmdlet has been added to allow you to detect and correct replication issues in the public folder database. This cmdlet replaces the Isinteg.exe tool. For more information, see Create a Public Folder Database Repair Request.