%1 (%2) %3Online defragmentation of database ‘%4’ terminated prematurely after encountering unexpected error %5. The next time online defragmentation is started on this database, it will resume from the point of interruption.

This Warning event indicates that online defragmentation of a database ended prematurely after encountering an unexpected error. The next time online defragmentation is started on this database, it will resume from the point of interruption.

This event generally indicates a problem with Exchange store memory, or a problem with the ESE database.

To determine the root cause of this event, you must examine the error codes listed in ESE event 705. You must also review the Application log for other ESE events and MSExchangeIS events. The following causes are the most common for event 705:

• The occurrence of error -1069 (0xfffffbd3) = Jet_errVersionStoreOutOfMemory in the description of event 705, other ESE events, and MSExchangeIS events in the Application log indicates that the store has run out of memory. If the version store runs out of memory, online defragmentation may not be able to complete.

• The occurrence of error -327 Jet_errBadPageLink and error -338 Jet_errBadParentPageLink indicate that a bad page link (error -327 or error -338) has been detected in a B-Tree. Error -327 indicates Jet_errBadPageLink and error -338 indicates Jet_errBadParentPageLink. A bad page link error indicates corruption in the database at the ESE level.

• The occurrence of error -1018 or Jet_errReadVerifyFailure indicates that there is a checksum error on a database page. -1018 errors also indicate database corruption on the ESE level, and are usually caused by hardware, controller, or file system level problems related to hardware.

To resolve this warning based on -327, -338, and -1018 errors, try one or more of the following:

• Check the Application log carefully for related events and patterns that may relate to this event. Check the System log carefully for related events and patterns including any errors related to hardware, drives, controllers, or the file system. If there are any such errors, replace the hardware, update the hardware system files, or repair the file system to prevent any future errors. Do this before proceeding to the next step

• If the Exchange store database is running, use ExMerge to merge your data to .pst files, delete the database, create a blank database, and then run ExMerge t databases to a blank database.

• If the database is running, you may also move all the mailboxes to another store, delete the affected database, create a new database, and then move all the mailboxes back.

• If the Exchange store database will not mount, the suggested remedy is to restore from online backup before the errors appear in the Application log.

• If the Exchange store database will not mount and there is no backup, the last resort is to repair the database by running eseutil /p and then repeatedly running isinteg -fix until there are no fixes reported. Finally, run ExMerge, create a blank store, and use ExMerge to move the data back in.

For more information about resolving -1018 errors, see 314917, Understanding and Analyzing -1018, -1019, and -1022.

If you notice -1069 errors in the Description section of MSExchangeIS events in the Application event log, contact Microsoft Product Support Services for help in troubleshooting this issue.

For information about ESE error codes other than the ones explained in this topic, see the following Microsoft Knowledge Base articles:

• 266361, Extensible Storage Engine 98 Error Codes 0 to -1048

• 266367, Extensible Storage Engine 98 Error Codes -1051 to -999999

If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.