Exchange server is the most secure way to communicate through emails, which also works as a virtual postbox. Similar to other email programs, Exchange server also stores files and their respective information in its own database, which is known as Exchange database. This database is the collection of following files:
1. Transaction log: Transaction log records all the modifications done to the internal memory of Exchange database. It is denoted as (*.log) file extension.
2. Checkpoint files: Checkpoint files records the history of logged transactions in the on-disk database files.
3. Database file: It is the most important content in the Exchange database. The file extension of Exchange server database file is EDB. It stores all essential files available in your Exchange server along with the available items in the mailbox like emails, contacts, tasks, calendars, journals, and notes in their appropriate folder. EDB is also named as Extensible Storage Engine (ESE) Database file.
EDB can be classified into two major categories:
1. Private EDB File or priv1.edb:
Private EDB stores confidential communications in the Microsoft Exchange Mail Server. It stores emails sent by a sender to an individual user. The default location of private EDB file is shown in the chart as given as below:
2. Public EDB File or pub1.edb:
Public EDB stores general communications (which is common for all) in the Microsoft Exchange Mail Server. It stores emails and attachments shared in a group. The default location of Public EDB file is shown in the chart as mentioned as below:
There are two types of corruption in Exchange database: Physical and Logical. Physical corruption occurs in the page level. Whereas logical corruption occurs in the database and Application level.
Physical corruption: Physical corruption occurs when the drive is damaged or other hardware system fails. The physical corruption leads to the crashing of entire system and it stops functioning.
User receives the following error in Exchange Server Application Event log as discussed in the table.
Microsoft provides a free utility called ESEUTIL utility to repair the above crashing issues in Exchange database.
Logical Corruption: Logical corruption occurs due to virus, trojan, worm attacks, or ESE engine failure, which may result in the corrupted or missing database. Logical corruption is usually difficult to repair. So, to test the inconsistencies in the database, Microsoft offered ISINTEG command to repair the crashing issues arise in Exchange database.
There are various different reasons that may cause logical error in Exchange database. Some of them are as follows:
Virus Attack: Sometimes several viruses, worms, or trojan may intact the original data of Exchange server and made Exchange EDB file inaccessible. In this situation, users need an appropriate tool to repair a crashed exchange database file.
Dirty System Shut-down: Dirty System Shut-down is the most notorious factor of an EDB file corruption. This problem appears when the transaction of an information is in progress and suddenly power fails which shuts-down your system automatically. This situation also obstructs supply and suddenly shut down Exchange server. Due to this reason, the EDB files attached with the log file gets crashed and shows an error message as shown as below:
The above error message is displayed when the EDB file is corrupted. Thus, repairing the crashed EDB files with safety is the prime concern for the users. So it is very important for the user to search for the dirty system shut-down.
The above article discusses all basic information of Exchange server database including its types. The classification of EDB file extension is also discussed properly along with both the physical and logical corruption occurrs in Exchange database. So, try to repair the crashed EDB file from last taken backup. If backup is not available and problem still persist then users can defrag the database using PowerShell ESEUTIL/d command and executing ISINTEG to synchronize the log sequence. As discussed above ESEUTIL and ISINTEG is a free utility provided by Microsoft to easily recover the Exchange server offline database.