%1 (%2) %3 Database %4: Page %5 failed verification due to a flush-order dependency mismatch. This page should have flushed before page %6, but the latter page has instead flushed first. Recovery/restore will fail with error %7. If this condition persists then please restore the database from a previous backup. This problem is likely due to faulty hardware “losing” one or more flushes on one or both of these pages sometime in the past. Please contact your hardware vendor for further assistance diagnosing the problem.

This Error event indicates that Microsoft® Exchange Server was unable to verify the sequence of the pages in an Exchange Server database. Specifically, this event can be logged during a recovery operation if Exchange identifies that the pages are written out of sequence. If the pages of a database are out of sequence, the recovery or restore process fails.

To understand the cause of this event, it is helpful if you understand how transaction log replay works in coordination with the pages of an Exchange Server database. When a recovery operation runs, Exchange first makes sure that the logical page number written on the page is correct. Then Exchange makes sure that the page checksum is good. Changes for a page are associated with a sequence number in the log file.

Exchange includes the functionality to detect file-level damage to pages in its databases. The error associated with this event is specified in the description of the event.

The following are the most common errors that are associated with file-level damage to an Exchange Server database:

• -1018 JET_errReadVerifyFailure

• -1019 JET_errPageNotInitialized

• -1022 JET_errDiskIO

Error -1018 is the most frequently seen error. This indicates that an Exchange Server database has suffered damage at the file system level. Almost always, you will find the root cause for a -1018 error in one of the underlying systems that Exchange depends on, not in Exchange Server code itself. There are very few exceptions to this rule. The exceptions to date have been with regard to Exchange reporting a -1018 condition, not because Exchange itself causes a -1018 error.

Most -1019 and -1022 errors are also caused by a fault in an underlying system. However, you cannot rule out the chance that -1019 and -1022 errors might occur because of an issue unrelated to the file system.

For more information about -1018, -1019 and -1022 errors, see following Microsoft Knowledge Base articles:

• 237953, XADM: Erroneous -1018 error returned during online backup

• 230215, XADM: Backup Checksuming Not Performed on Single Processor Computers

• 314917, Understanding and analyzing -1018, -1019, and -1022 Exchange database errors

To resolve this event, do one or more of the following:

• Try to restore the Exchange Server database from backup. For information about how to recover Exchange Server databases, see the Exchange 2003 Disaster Recovery Operations Guide. For more information about recovering Exchange Server databases, see Microsoft Knowledge Base article 313184, How to recover the information store on Exchange 2000 Server or Exchange Server 2003 in a single site.

• Try to repair the database using the Exchange Server Eseutil and Isinteg utilities. For information about repairing Exchange Server databases see “Repairing Exchange Databases” in the Exchange 2003 Disaster Recovery Operations Guide.

• Run the Exchange Server Disaster Recovery Analyzer Tool on the servers in your Exchange Server environment. The Exchange Server Disaster Recovery Analyzer examines an Exchange Server deployment when an Exchange Server database does not mount. Based on the problem found, the tool automatically generates step-by-step instructions to bring the database online. The Exchange Server Disaster Recovery Analyzer can be used with Exchange 2000 Server and Exchange Server 2003. For information about how to download and run this and other Microsoft Exchange Server Analyzer tools, see the Microsoft Exchange Server Analyzer Tools Web page.

• Contact your hardware vendor for more help diagnosing the problem. For example, hardware vendors may be able to help you identify any firmware or device driver issues that may be causing the problem.

For information about how the Microsoft Information Technology group (Microsoft IT) recovers from -1018 errors, see Exchange Server Error –1018: How Microsoft IT Recovers Damaged Exchange Databases.