SUMMARY
This article addresses an issue that causes Exchange differential backups to fail, where Exchange full backups are successful.
ISSUE
Applies To
RecoveryOS version 5.0+
Client Agent software version 5.0+
MS Exchange 2003/2007/2010/2013
Symptoms / Description
ISSUE: Exchange differential backups are failing though Exchange full backups are successful. In the Windows event logs, the following error occurs after the Exchange differential backup is attempted.
Event Type: Error
Event Source: MSExchangeIS
Event Category: Exchange VSS Writer
Exchange VSS Writer (instance xxx) failed with error code 1296 when collecting private metadata information for storage group 'IDE Storage' in preparation for backup.
For more detailed information on backup failures and performance issues see Unitrends KB 5062 - Backup Failures and Performance Issues
RESOLUTION
To resolve this error, turn off circular logging, restart your Exchange server and then run a new full backup. To disable circular logging, refer to MS KB article 314605.
Third-Party Sources
Best Practices of Exchange Server Preventative Maintenance
Exchange Circular Logging and VSS Backups
Circular Logging Prevents Backing Up Your Small Business Server
What is Circular Logging?
Clearing the confusion around circular logging
CAUSE
Circular logging manages Exchange transaction logs, truncating this logs to conserve space. Exchange differential backups rely on a complete log chain to perform a successful backup. When circular logging truncations a log in the log chain which is required for a successful Exchange differential backup, this cause the subsequent Exchange differential backups to fail.