Checksum Errors on Exchange Server Database Pages

A corrupted or damaged Exchange Server database exhibits abrupt behavior while normal database operations. However, you can deduce the root cause of the issue and sometimes, solution to the problem by application log entries. You should restore the corrupted database from the last backup, if is available and valid. In case of database issues, you are recommended to use EDB Recovery Software to repair the damaged database.

For example, consider you use Exchange Server 2003 or Exchange Server 2000. You use Exchange online backup to backup your Information Store database and fail to do so. When you view the application log in Event Viewer, you encounter the below error message:  

“Information Store (2240) The database page read from the file "E:\program files\exchsrvr\mdbdata\priv1.edb" at offset 204275712 (0x000000000c2d0000) for 4096 (0x00001000) bytes failed verification due to a page checksum mismatch. The expected checksum was 303571876 (0x121823a4) and the actual checksum was 303571940 (0x121823e4). The read operation will fail with error -1018 (0xfffffc06). If this condition persists then please restore the database from a previous backup.”

This error is logged with event ID 474.  

Cause

Error 1018 indicates JET_errReadVerifyFailure error.

It results because of checksum errors on database pages. The prominent reason for this error to occur is Exchange database corruption due to file system errors. If the disk subsystem is suffering from issues, like defective disk drivers, faulty controller or outdated or incompatible firmware, this could result into Exchange database corruption.  

Solution

You can solve these problems by these methods:
1.Try to perform backup using different storage group located on a different server disk.
2.Diagnose and troubleshoot your Exchange Server running system for possible hardware issues
3.Update your system with the latest firmware and drivers updates available
4.If a clean data backup is available, restore your database
5.Perform hard repair of the database using Eseutil /p in case no suitable backup is present
6.Eseutil /p is a destructive repair operation that could delete the corrupted database pages.

To prevent the consequences, you should use safe EDB Recovery utilities. EDB Recovery Software are powerful tools to examine, repair and restore damaged Exchange databases using efficient scanning algorithms. These tools provide you graphically rich user interface and advanced features that result complete database repair.

Stellar Phoenix Mailbox Exchange Recovery is a fully-competent EDB Recovery Tool to systematically repair damaged Exchange databases created with Exchange Server 5.5, 2000 and 2003. It provides safe EDB Repair and extracts all user mailboxes by converting them into Outlook usable .pst files. The tool can recover all email messages, notes, journals, tasks and other objects.

Exchange Server Store Fails with Server-Specific Error 0

Exchange Information Store Service might become unresponsive if the database store is corrupt , which prevents you from accessing the data stored in. Information Store, being the central data storing component, stores all the user mailboxes and other information. So, to restore it, you need to apply your last online backup or perform database repair using Eseutil utility.

If all measures fail, Exchange Recovery Tools can help repairing and restoring them. When using Exchange Server, you might come across these symptoms: 1.Exchange Server and/or Information Store fail to start and work 2.Trying to start Information Store gives the below error: “Windows could not start the Microsoft exchange information store on local computer.

For information, review the system log. If this is a non-Microsoft service, contact the service vendor, and refer to service-specific error code 0.” 1.Attempting to start any exchange event prompts another error as below: “Could not start the microsoft exchange event service on local computer. Error 1068:The dependency service or group failed to start.” 1.When you view the event viewer, it displays errors with Event ID 7001 and/or 7024 suggesting that Information Store service could not be started Cause General reasons that fail to start Information Store service are as follows: 1.Disk permissions issues, for example Windows Registry or file system 2.Disk space missing for Information Store files 3.One or more application files are missing or damaged 4.Information Store corruption.

This could also result due to damaged messages in the store Solution Applying following solutions can help you recovering from the situation: 1.Ensure for correct disk permissions and proper disk space. Empty disk space if required 2.Try reinstalling Exchange Server 3.Run Eseutil utility to repair (/r switch) and perform offline defragmentation (/d switch) of the Information Store databases. If this fails, consider using third-party Microsoft Exchange Recovery products to repair and restore databases while valid data backup is unavailable.

Exchange Recovery Tools are specially designed utilities with self-descriptive interface and high-end database repair algorithms. The software are easy to install and implement as provide complete documentation with user-friendly interface. Stellar Phoenix Mailbox Exchange Recovery is an advanced utility that employs powerful scanning algorithms to repair a damaged Exchange database. It supports Exchange Server 5.5, 2000 and 2003. It is a safe Microsoft Exchange Recovery utility with impressive features. The tool extracts user mailboxes in individual .pst file format files.

How to Solve Event 465 in Exchange Server?

An Exchange public store or mailbox store of a storage group can be mounted using Exchange Management Console or Exchange Management Shell. This makes the databases ready for use. For any reason, if the process fails, it leads to data inaccessibility. Database mount failure primarily suggests that one or more storage group components are faulty. However, if one or more databases are corrupted, you should use eseutil utility to repair it. Alternatively, you can apply the last good backup or use a powerful .EDB Repair utility to repair the corrupted database.

For instance, suppose you try to mount public or mailbox store in Exchange Server. The operation fails and the application event log reports the below information message: Event ID: 465 Source: Ese98 Type: Error Computer: Server1 Information Store (2184) Corruption was detected during soft recovery in logfile C:\Programme\Exchsrvr\mdbdata\E00000E8.log. The failing checksum record is located at position 6531:471. Data not matching the log-file fill pattern first appeared in sector 6600. This logfile has been damaged and is unusable. For more information, click http://search.support.microsoft.com/search/?adv=1. Error 465 is usually accompanied with error 477 that informs checksum mismatch and suggests you to restore the logfile from backup.  

Cause The prime cause of error 465 to occur is transaction log file corruption, specifically Edb00000E8.log file.  

Solution You should remove the corrupted log file to achieve recovery. To do so, you must first find out the storage group, which is affected from this corruption and then follow these steps: 1.Dismount all the databases of affected storage group and perform its offline backup. 2.Run eseutil /mh tool to make sure if the databases exist in consistent state. 3.If all the databases report 'Clean Shutdown' state, move out all the log files from Exchsrvr\Mdbdata folder. 4.But if databases exist in 'Dirty Shutdown' state, perform soft database recovery using eseutil /r 5.On unsuccessful attempt of soft recovery, you can restore the database from last Exchange backup 6.In cases when no valid backup is available, you can try repairing the database using eseutil /p, which performs hard repair. 7.

The hard repair of Exchange database causes corrupted pages to delete. Thus, it is suggested to use a third-party EDB Repair Tool for more effective and safe database repair. EDB Repair software employ advanced scanning algorithms and provide you easy-to-implement user interface.

Stellar Phoenix Mailbox Exchange Recovery is a full-featured EDB Repair Software to perform systematic repair of damaged Exchange databases created with Exchange Server 5.5, 2000 and 2003. It is a safe EDB Repair Tool that extracts all user mailboxes by converting them into individual Outlook usable .pst files. The tool can recover all email messages, notes, journals, tasks and other objects.

Exchange Server Database Unmountable After Applying SP3 or Later

Service Pack 3 (SP3) and later for Exchange Server include several security and performance enhancing improvements that provide the user more customized experience. You are recommended to always perform a complete database backup before installing the update on your Exchange Server computer. This is because installing the update and upgrading Exchange Server might render the database unmountable. In such cases, you require to use your current database backup to restore it or perform effective Exchange Recovery using third-party tools. To exemplify, consider that you use Exchange Server 2000 SP2 and attempt to upgrade it to Exchange Server 2003.

Resolving Error 501 in Exchange Server

Exchange Server Information Store databases support transaction logging i.e. before committing any data to the database, it is first written to transaction logs. If your database is ever forced to perform recovery, these transaction logs replay and restore the database to a working state. When an Exchange Server Information Store database corrupts, it marks an event indicating the root cause of the issue.

You can deduce the problem and thus, take corrective measures to solve it. In cases, when no backup is available to replace the damaged database and ESEUTIL utility also fails to repair, you need to use an effective Microsoft Exchange Recovery utility that could repair and restore the damaged database. For an instance, you might receive the below event ID in Application log of Event Viewer: Date: date Source: ESE Time: time Category: Logging/Recovery Type: Error Event ID: 454 User: N/A Computer: Servername Description: Information Store (2184) Database recovery/restore failed with unexpected error -501 Cause Event 454 generally indicates database corruption that occurs while restore or recovery operation. Error -501 corresponds to hexadecimal value 0xFFFFFE0B. It represents JET_errLogFileCorrupt error and shows that the recovery operation has failed because of log file corruption.

Solution You need to solve the given issue by following these steps: Check if all database files are consistent. If they are, you can move all corrupted log files that are contained in Exchsrvr\Mdbdata folder and then try to mount the Information Store If applying the above step doesn't solve the issue as databases are not consistent, you need to restore the corrupted databases from backup. In case, no suitable backup is present, you can execute eseutil /p command to repair the damaged databases If the error stil persists, use a powerful and safe third-party Exchange Recovery Tool to scan and repair the damaged database. Microsoft Exchange Recovery software are non-destructive tools designed with advanced technology to repair the corrupted database.

These tools provide you self-explanatory interface and provide advanced set of features. In addition, you can use these products in any case of logical database corruption. Stellar Phoenix Mailbox Exchange Recovery is a fully-competent Exchange Server Recovery tool to systematically repair damaged Exchange databases created with Exchange Server 5.5, 2000 and 2003. It provides safe Exchange Recovery Tool that extracts all user mailboxes by converting them into Outlook usable .pst files. The tool is capable of recovering all email messages, notes, journals, tasks and other objects.

JET_errBadPageLink, Database corrupted Error in Exchange Server

An Exchange Server Information Store might get corrupted due to several errors, including unexpected shutdown and network errors. Corruption might involve any database files, called .edb files, that reside in Exchsrvr\Mdbdata folder. While Information Store corruption, you might observe server behaving slowly, Information Store Service not starting or not stopping, email delivery issues and several errors showing that the database is inconsistent. You should use your backup to restore such corrupted database or run ESEUTIL utility to repair it. However, if none of the solutions works, you should use Exchange Repair Software that could repair and restore a damaged Exchange database. For an instance, consider that you run ESEUTIL /D utility to defragment your database and the process fails. When you view the Windows NT Application log of Event Viewer, you come across the below error message:

Page Checksum Mismatch in EDB File and Recovery

Microsoft Exchange Server uses checksum procedure to confirm for database pages integrity. You can use ESEUTIL utility with /K switch to verify page-level integrity of Information Store databases. If it results errors, one or more of your database pages are corrupted that you need to restore from the available backup. In case no suitable backup is present, you require to use an EDB Recovery Software.

You might come across any of the below symptoms with your Exchange Server: Error “Database page read failed verification because of a -1018 error (page checksum mismatch). This page level error is often caused by driver, firmware, or hardware issues.” Users fail to send or receive email messages You receive -1018 checksum error when you attempt to perform online backups You encounter -1018 checksum mismatch error when you try to defragment the database At client side, Microsoft Outlook is not started Cause Such behavior is usually exhibited when a database page read fails verification. As indicated, this occurs due to mismatch of page checksum. The referenced page stored on Exchange EDB file is corrupted. Note: The error indicates inability to retrieve data from EDB database file, which might also occur due to RAM or firmware issues. Solution You are recommended to follow these suggestions to isolate the given issue: You should run system diagnosis to check for RAM or firmware related concerns. You can deduce the issue if the corruption problem is frequent Try upgrading the firmware and system BIOS to their latest versions available Repair the damaged EDB files using eseutil /P.

You should then execute eseutil /D followed by isinteg -fix If ESEUTIL repair utility fails to fix database corruption, you need to migrate the database from recent backup. However, while any concerns related to restoring from backup, you should Recover EDB file by using third-party special purposed tools. EDB Recovery Software are high-end tools with powerful, yet safe, algorithms to examine, repair and restore the damaged Exchange Server database. These applications are reliable tools that work efficiently and successfully extracts all user mailboxes without harming the actual database contents. Stellar Phoenix Mailbox Exchange Recovery is a comprehensive tool to safely extract all the mailboxes from damaged databases created with Exchange Server 5.5, 2000 and 2003. It is a safe EDB Recovery Tool to Recover EDB and all objects including emails, email properties, tasks, drafts and more.

Exchange Errors due to Undetected Page Removal while B-tree Split Operation

EDB Repair - EDB Repair Tool Microsoft Exchange Server storage groups are consisted of mailbox store and public folder store. Each mailbox store is further made up of database set comprising of two files: Priv.edb and Priv.stm. Similarly, each public folder store database set contains Pub.edb and Pub.stm files. For any reason if Information Store databases get corrupt, you might experience symptoms like slow performance, abrupt behavior while normal operations and most often, JET errors. If an updated data backup is available, you are recommended to restore from it to solve these problems. In case no valid copy exists, try running built-in ESEUTIL /P utility or safe EDB Repair Tool.

 For instance, when using Microsoft Exchange Server, you may observe any of the below symptoms with information store databases: 1. You run ESEUTIL /D to attempt offline defragmentation of the database, but fail with -1601(JET_errRecordNotFound) or -1603(JET_errNoCurrentRecord) error 2. Error -1069 error (JET_errVersionStoreOutOfMemory) while normal database operations 3. Application log reports an error with Event ID: 1101 4. You run ESEUTIL /G /V /X in Exchange Server 5.5 and receive JET Error -1206 (JET_errDatabaseCorrupted). Cause The Information Store service might violate access because of encountered corrupt data. When trying to insert a record in B-tree, the Exchange engine might find a record with same primary key value, marked for deletion. In such cases, it undeletes the node by updating its content with that of new record and might even change the size of record. Now, if this size is too large for the page, the database engine performs b-tree split operation.

The information store may become unresponsive or data might get corrupt if Exchange Server tries to re-latch the pages while the record has been actually removed by information store cleanup thread. Solution You can recover from such problems by applying these measures: 1.Execute database consistency checker to check for corrupted and/or orphaned LVs 2.For correcting corrupted and orpahned LV errors, you need to run ESEUTIL /P /X followed by offline defragmentation 3.Perform offline defragmentation if only orphaned LVs are reported 4.In case of corrupted LVs, you should run ESEUTIL /P /X followed by offline defragmentation If applying these measures doesn't fix the database corruption problem, you should restore from the complete database backup or use a EDB Repair Tool in case of valid backup unavailability. 

EDB Repair utilities are graphically rich tools incorporated with high-end scanning algorithms to repair and restore damaged Exchange databases at a safe location. Stellar Phoenix Mailbox Exchange Recovery is an advanced utility that employs high-end scanning algorithms to repair a damaged Exchange database. It supports Exchange Server 5.5, 2000 and 2003. It is a safe EDB Repair Tool with impressive features. The tool extracts user mailboxes in .pst file format.