How to fix Exchange Error -501 (0xfffffe0b) JET_errLogFileCorrupt

Log files are the most critical component of Exchange server, as they play a significant role in recovery of Exchange when database is in shutdown stage. All Exchange admin’s are aware of the fact that even small errors in Log files may lead to serious problems such as Unable to Mount Stores, Exchange Server shutdown. One such error is JET_errLogFileCorrupt – which is faced due to log files corruption and may lead to Exchange corruption if not properly handled. Let’s check what this error is and how to tackle this.

What is Exchange Exchange Error - JET_errLogFileCorrupt ?

When user is unable to mount information store database due to the corrupt log file, there Exchange Error JET_errLogFileCorrupt is displayed.  Improper handling of this error may lead to inconsistent stage of database. For handling inconsistent stage you may need to use either eseutil.exe or any professional Exchange Recovery software. Here some common causes, resolution techniques, manual as well as professional discussed in this article.

Cause of this error: Corruption in log files is the main reason behind this error. Lost, damaged files or because of corruption in header of log files this error may be shown. After this error user gets unable to mount data to the database.

How to check your Log files are damaged?

To confirm that your log files are damaged or not. Follow certain steps:

1. Open command Prompt window

2. Change to the folder where the log files are located.

3. Type command: eseutil /ml Enn

If this process terminates with error -501 it means, it means your Log files are corrupt

Operation terminated with error -501 (JET_errLogFileCorrupt, Log file is corrupt)

Than you may need to resolve this error by following procedure mentioned below.

How to Resolve this Manually

To resolve this error manually, at first you need to remove your damaged log files from database and then restore them back, from the backup. After that you need to execute eseutil.exe to regenerate log files.

Here some steps had been discussed which could be followed to resolve this error.

1.  Try to locate a copy of Log files

2.  Discard the damaged log file

3. Restore backup of the Exchange database

4.  Perform Hard Recovery

Try to locate a copy of Log files: As a first solution, try to find a copy of Log files in working condition from Exchange online backup or from previous server backup. However if you are not having backup you may need to repair corrupt Log files using Hard recovery by Eseutility or by professional software for Exchange recocery.

Discard the damaged log file: If you find a copy of Log files in working condition, it means you can delete previous corrupt log files and restore them from backup but before that you need to discard damaged log files.

Restore backup of the Exchange database: After deleting corrupt Log files, now it’s time to restore Exchange database from backup. But if you having old copy of the database in that case you will lose all the data saved after creating backup, an alternate solution is to try to remove corruption using hard recovery.

Doing Hard Recovery for Log File repair: After restoring data from online backup, you may need to perform hard recovery to repair damaged log files. But before performing hard recovery it is advised to take a backup of the folder containing log files as data may be lost during this process.

1. Once restoration of the database is complete a file names ‘restore.env’ will be created at temporary folder ‘C:\Temp’. This will contain all logs that were backed up without being committed to the database.

2. After that execute command Eseutil /cc “Path of the restore.env containing folder”.

3. After complete execution of this command restore.env file will be deleted.

However it is extremely difficult to perform Hard recovery and to replay damaged log file into a database as along-with matching up databases and logs by signatures user may also need to keep record of checkpoint value in the database header, risk of replaying wrong log files into the database is also there. So rather than going for this complex process, it is advised to use a professional Exchange Recovery solution for solving this Error.

Using professional solution: As this solution of Eseutility may not work for you all the time. In case backup of exchange database is not there this solution will not work .There you may need to take help of professional Exchange recovery software which can thoroughly scan your damaged database and repair corrupt edb files providing access to Exchange data again.

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How to Recover Corrupt Information Store Database of Exchange 2010

Information Store is one of the most important modules of MS Exchange Server that is accountable to store database files of MS Exchange Server, known as EDB. There are cases when Information Store comes across adverse circumstances and gets corrupt, which consequences in loss of all the stored data in EDB files. Here is how you can recover from corruption in Exchange 2010 information store.

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How to fix Outlook error “0x8004010f” - Outlook data file cannot be accessed

From all OST file corruption causes, Outlook error "0x8004010f " is one of the most commonly seen Outlook error, which is generally seen with OST file corruption due to synchronization problem in OST file. MAPI error code “0x8004010f” popup in situations where user is trying to synchronize offline address book, during sending/receiving operations means trying to download that OAB files where Outlook profile is incorrectly configured. New Exchange client users also complaint about this error quite frequently as Exchange takes around 24 - 48 hours to generate offline address book for a new user and if during this time period any Outlook client try to download Offline Address Book, this error would be displayed. Here in this article some symptoms, most common causes of this error and some commonly used methods to fix the error have been discussed.

Symptoms:

When a user tries to synchronize OST file on Exchange Server, he may get this error message in Sync Issues folder:

0x8004010F: Outlook data file cannot be accessed.

or

0x8004010F: The operation failed. An object could not be found.

After encountering the above error,user receives the error message given below in Microsoft Office Outlook when he tries to send an email,

“Task ‘Microsoft Exchange Server’ reported error (0×8004010F): ‘The operation failed. An object could not be found.’”

If this error occurs,outlook terminates the process of synchronization and at that time, client couldn’t connect to his Exchange server Mailbox.

Cause of this Error: There are multiple reasons which could be responsible for the generation of this error in Outlook:

1. Multiple OAB Version folders exist of the same type.

2. OAB lists objects have either missing or incorrect address list.

3. Clients are trying to download that OAB files from a public folder store which have not received the replicated updates.

4. Information Store has invalid Entry ID pointing to folders where clients have nothing to download.

5. OST file had become either corrupt or unusable.

Manual way to resolve this Error: To resolve this error manually, user first need to track the exact location of your default Outlook data file and after that create a new Outlook profile and then Configure that new Outlook profile as your default profile. The procedure has been discussed below in detail within three steps.

Step:1        Tracking the Location of default Outlook data file :

1.       Go to Start -> Click Control Panel -> Mail Setup.

2.       From Mail Setup - Outlook dialog box, click Show Profiles.

3.       Choose your current Outlook profile, and then click Properties.

4.       In Mail Setup - Outlook dialog box,click Data Files

5.       In Account Settings dialog box, select Data Files tab .

6.       Note name and location of the default data file of your profile& click Close.

 Step: 2     Creating a new Outlook profile:Create an Outlook Profile with IMAP or POP3 email account using an auto account setup.

Step: 3    Set newly configured Outlook profile as a default profile: 

1.  In New Outlook Mail dialog box, select General tab& select Always use this profile.                  

2.  From drop down menu of Always use this profile, select the new profile.

Note: However if above mentioned steps did not work for you, then probably your Outlook file could be corrupt. In those situations it would be best to use a professional OST to PST conversion software using which corruption of OST file could be cured. Many OST to PST conversion software are available in market to fix OST file corruption and solving synchronization issues of OST file. But before choosing any such tool do complete research, ensure that it is compatible with the current version of MS Outlook and Windows OS which you are using.

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Why You Should Migrate From Exchange 2010 to Exchange 2013

If your organization has been planning to migrate to Office 365, then there is a convincing reason that it offers users a benefit of unlimited storage space.

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How to fix Exchange Error “JET_errInvalidLogSequence” (0xfffffdfd)

This is a common Exchange error which generally occurs due to log files problems such as when some particular log files are missing from the sequence or do not match with other log files. Main reason behind this error is invalid log signature and log creation time mismatch. In situations where some log files are not present in database or corresponding header is unable to find matching file in the database, this error is displayed. However this error could also be seen in circumstances where database is restored multiple times, because at that time Exchange is left with mixed log streams. In this article few inbuilt utilities has been explained to fix this error.

How to Repair log files:

As log files are the main cause of this error, so to fix this error at first log files needed to be fixed. To fix log files in Exchange Server there is recovery mode, which use some inbuilt utilities like Eseutil /r , Eseutil /p  helps to repair damaged Log files.

Repairing Log files using Eseutil /r  :

Eseutil /r works in Recovery mode of Exchange Server. Recovery mode which is a process of playing transaction log files into database so as to repair Log files. In exchange normally two types of recovery are done.

1. Hard Recovery using Eseutil : This is less seen recovery mode of eseutility , which is used when transaction log files areto be  replayed into online backup. Hard recovery can be done with Eseutil by using the Restore mode.

Doing troubleshooting when ESE engine is forced to replay the transaction logs, this is known as a hard recovery , hence Eseutil /r.

2. Soft Recovery using Eseutil : This recovery occurs when a database is re-mounted after unexpected stop of Exchange, or when transaction logs are to be replayed into offline backup of database.

This recovery process replays the logs after the last checkpoint.  When Exchange Database is dismounted or stopped, log files start to pile up in the database, which could lead Exchange to dirty shutdown state because of missing transaction files.

After Software recovery when Mailbox store starts again, all of the unattached transactions files of those logs are written in the database, remounting those transaction files may cause a built-in soft recovery routine.

Controlling the Checkpoint File in Software Recovery

While performing soft recovery, Exchange at first check recent transactions files, and then after that from last checkpoint it reads pointers in E00.chk, on the basis of that information it knows which transactions files to commit and which to roll-back, so as to bring database in consistent state.

While running soft recovery, normally users want to delete/ move the checkpoint file as they want to safely rerun all transaction logs into database.  Those checkpoint files could be controlled during a soft recovery, by adding the /S switch to the recovery command:

Eseutil /r E00 /S

d:\checkpoint\

Working of Eseutil /r :

Working with Eseutility in repair mode is not as easy task as it looks, you cannot run /r in ordinary situations, as improperly executed  eseutil /r  may result you opposite results. This solution is to be used when all other solutions has been failed to get the server working. In situations where you had restored Exchange  database and you are unable to mount the store then also you can take help of Eseutil /r.

While performing recovery using Eseutil /r utility at first, take backup of Exchange database so that in case something bad happens, database could be restored from that.

Then navigate to the folder which is containing those transaction logs, and run:

 eseutil /r e00 /i . 

Note the sequence /r e00 /i should be correct.  If your  base log is e00  and not some other numberand your  storage group is with multiple stores, in that case user have to dismount all stores before running the /r switch. 

Repairing Log files using Eseutil /p  :

If log files are not available, still you can bring your exchange database in consistent state, by executing /p switch of ESEutil. Syntax which could be used to recover Exchange database without log file is :

“eseutil/p<database_name>”

D:\Program Files\Exchsrvr\Bin>eseutil/p

 “D:\Exchsrvr\Mailbox Store(SERVER).edb”

  

Note : Using this method to bring database in consistent stage is not as simple as it looks ,as this may lead user to data loss , in situations where Eseutil is not properly executed , or any structure improvement calls raised because of deletion of internal pages or if there are broken links between the table. In those situations user may need to rebuild database using offline defragmentation and correcting B-tree structure of database which obviously become a lengthy and complicated task with Eseutility.

An alternative to this complex process is going for professional Exchange recovery tools which can just calls for database file availability (healthy/offline/corrupt state) to get consistent DB. Exchange Recovery software repairs log files and recover Exchange database  from Dirty shutdown state providing access to exchange data again.

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