How to identify the corrupt Exchange database and Repair them.

Published by Jacob Martin on November 7, 2013

Microsoft Exchange server offers an effective messaging environment which is very powerful and reliable. This program helps to send or read emails at offices, shops, commercial or any other places through its networking program. It even allows the users to perform multitasking such as sending emails, instant messaging, file archiving, task scheduling, calendaring and many more.

It saves users email records or data into its Exchange database or EDB folders. These EDB folders comprises of EDB, Checkpoints and Transaction log files. EDB files are known as primary Exchange database and it is crucial for running email system based on Exchange server smoothly. So sometimes due to various reasons it may hinder the smooth functioning of MS Exchange Server basically due to-

• Dirty Database Shutdown- Which is the most common reason for crash of Information Store while accessing the corrupt database. To restore the database in this stage can be recovered though updating backup copy and then re-synchronizing it with transaction logs.
• Stored Information also fails to start due to crashing of hard disk or by presence of bad sectors within it. These bad sectors of the Hard disks which stores data leads to problems while accessing or mounting the data from the database.
• These Exchange database may get prone to virus attack or to some other malicious applications which leads to file header corruption and leads to damage. So once the EDB file header gets corrupted it restricts the access to the stored mailbox items.
• If Exchange Server Database or Information encounters Physical Damage. It can be identified or detected easily. The log files would be out of disk space or there will be a hardware failure with log file disk. The hardware, operating system or device driver will be returning errors. And the data in the disk will be not same as the data that was originally written on the disk.
• Due to installation of malicious codes.
• Due to broken or twisted LAN cable.
• Due to slow internet connectivity and many more.

 “Error 4294966746: JET_errDatabaseInconsistent” is the most common error message that is the indicator of Exchange Server corruption.

 How to recover EDB software-

Microsoft Exchange Server provides two types of inbuilt diagnosis and recovery tools which are Eseutil.exe and lsinteg.exe. Both of these utilities consist of troubleshooting commands and many Exchange database corruption issues.

The Eseutil tool offers dual database recovery switches:

1. Eseutil/P: It is known as Eseutil hard recovery option. It helps to troubleshoot Exchange corruptions such as Exchange disasters. But this may lose EDB file’s crucial data, which is easily repaired by Eseutil/P command.
2. Eseutil/R: It is known as Eseutil soft recovery option. It helps when EDB files encounters minor issues or only few Exchange database files damage.

To start eseutil recovery command we have to check the status of the EDB file whether it is mounted on the Exchange Server or it is in Offline Mode:

Eseutil/mh “:C:Program filesExchsrvrMDBDataPrimary name.EDB”

This command return backs from “Dirty Shutdown” state, which means EDB file has switched into the offline mode and needs repair using Eseutil/R command which is-

Eseutil/R “:C:Program filesExchsrvrMDBDataPrimary name.EDB”

If cannot recover EDB files from corruption with the help of Eseutil/R then use Eseutil hard recovery which includes the following command-

Eseutil/P “:C:Program filesExchsrvrMDBDataPrimary name.EDB”

After recovering EDB files such as Priv1.EDB or Pub1.EDB, it requires to compact the repaired file using Eseutil/D command:

Eseutil/D “:C:Program filesExchsrvrMDBDataPrimary name.EDB”

Then check the consistency of all the Exchange mailbox stores of MS Exchange Server using Isinteg command:
Isinteg- s (Name of Exchange Server)- fix- test all tests

Repeat Isinteg command till it does not show zero error in MS Exchange Server. After successful Eseutil and Isinteg commands execution, it requires mounting of repaired mailbox store or Exchange Management Shell or Public Store on the Exchange Server using Exchange Management Console. But, Exchange identification and curing tools has certain limitations:

• Eseutil and Isinteg work only on offline EDB files.
• It fails to fix critical Exchange corruption issues.
• It takes a lot of time in recovering large EDB databases

EDB Repair Tool-

The best way to recover corrupted Exchange databases from backup files using third party EDB Repair Tool. You may come across many EDB Repair Tools on Internet but they flawlessly recover inaccessible mailbox stores or through many public stores of the organization. I would like to recommend such kind of EDB Recovery Tool which is very efficient to restore inaccessible EDB files. It successfully retrieves large Exchange mailbox information from damaged and corrupted EDF files.