DOCUMENT:Q168357  16-OCT-1999  [exchange]
TITLE   :XADM: Event ID: 24 Asynchronous Read Page Time Error
PRODUCT :Microsoft Exchange
PROD/VER:winnt:4.0,5.0,5.5
OPER/SYS:
KEYWORDS:kbusage exc4 exc5 exc55

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Exchange Server, versions 4.0, 5.0, 5.5 
-------------------------------------------------------------------------------

SYMPTOMS
========

Directory replication may stop and the Event Viewer Application Log may display
the following error:

   Event ID: 24
   Source:   EDB
   Type:     Error
   Category: Database Page Cache

The description may be similar to:

   MSExchangeDS ((198) ) Asynchronous read page time error -1018 (
   (1:21534, 21304)
   (0-24430833), (0-60422491), 1298669031, 1900239879 ) occurred. Please
   restore the databases from a previous backup.

CAUSE
=====

The Directory database (Dir.edb) most likely has become corrupt. To discover
which database is corrupt, start the Windows NT Event Viewer and look in the
Application log for the following Event ID:

   Event ID: 39
   Source:   EDB
   Type:     Warning
   Category: Logging/Recovery

The description may be similar to:

   ((269) ) Unable to read header of database F:\Exchsrvr\Mdbdata\Dir.edb.
   Error -1206.

The file listed in the description is the corrupt database.

RESOLUTION
==========

To resolve this problem, do one of the following:

 - Restore Dir.edb from a previous backup.

   -OR-

 - Repair the bad page of data by running Edbutil.exe:

CAUTION: Edbutil.exe is a low-level Exchange database engine utility that
defragmentsand checks the consistency of the database. The repair option (which
is EDBUTIL /d /r <dbname>) attempts to repair bad pages or remove bad
pages if the repair is unsuccessful. If a page is removed using the repair
option, there most certainly will be data loss.

1. Make sure you have made a full backup of the Dsadata directory.

2. Make sure you have enough free disk space. You must have more free disk space
   than the size of the DIR.EDB file. This free space should be on the drive
   from which Edbutil.exe is run.

3. From the \exchsrvr\bin directory run:

   Edbutil /d /r /ds

MORE INFORMATION
================

If you receive an error running Edbutil /d /ds /r, you may need to specify the
entire path to the Dir.edb file. For example:

   edbutil /d c:\exchsrvr\dsadata\dir.edb /r

Refer to the Microsoft Exchange Administrators guide for more details on the use
of Edbutil.exe.

Additional query words:

======================================================================
Keywords          : kbusage exc4 exc5 exc55 
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2
Version           : winnt:4.0,5.0,5.5
Issue type        : kbprb

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND.  MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.  SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1999.