Backup is the important and easiest prevention step to safeguard your data on Exchange Server. In case of any mishap, you can easily restore your data from recent backup. But in some situations, while backing up your data, you might come across a number of error messages and the backup process fails. This behavior generally occurs due to corruption to the database and it renders all of your critical emails, notes, contacts and other data inaccessible. It results into data loss and require Exchange Recovery to be sorted out.

In a practical scenario, when you try to backup Exchange Server 2003 database, the following error occurs:
"WARNING: Portions of <mailbox store name> cannot be read. The backed up
data is corrupt or incomplete."

At the same time, a number of Events are logged into Exchange Server Application Event Log that may sound like the following one:

Event Type: Error
Event Source: ESE
Event Category: Logging/Recovery
Event ID: 478
Date: 14/09/2005
Time: 6:48:56 AM
User: N/A
Computer: MAIL
Description:
Information Store (2692) The streaming page read from the file "C:\Program
Files\Exchsrvr\mdbdata\priv1.stm" at offset 1245716480 (0x000000004a402000)

for 4096 (0x00001000) bytes failed verification due to a page checksum
mismatch. The expected checksum was 2777780870 (0xa5919286) and the actual
checksum was 2814150562 (0xa7bc87a2). The read operation will fail with
error -613 (0xfffffd9b). If this condition persists then please restore the
database from a previous backup.

Root of the issue

You may come across this behavior of Exchange Server due to any of the following reasons:
The Exchange Server Database (EDB) is corrupted and it can not be read
The STM (Streaming Internet Content File) is damaged

In both of these situations, the Exchange Server database can not be accessed and you need to go for Exchange Recovery by working around this problem.

Resolution

You can sort out this problem by repairing and restoring corrupted EDB file. It is best possible with the help of effective third party tools, known as Exchange Repair software. These programs are capable of thoroughly scanning damaged EDB file and extracting all of its mailboxes and their objects such as emails, contacts, notes, tasks, journal, calendar, personal folders and more.

Exchange Repair applications have self-descriptive and interactive graphical user interface that let you carry out easy and quick recovery without demanding sound and prior technical knowledge. Due to read-only and non-destructive demeanor, they do not change original contents of the database.

Stellar Phoenix Mailbox Exchange Recovery is the most advanced tool to repair and restore EDB files created using Exchange Server 2003, 2000 and 5.5. This software is designed for Microsoft Windows 2003, XP and 2000. It also recovers email addresses from Active Directory Store.