DOCUMENT:Q181798  02-APR-1999  [exchange]
TITLE   :XADM: Online Restore May Not Replay Log Files
PRODUCT :Microsoft Exchange
PROD/VER:WINDOWS:4.0,5.0,5.5
OPER/SYS:
KEYWORDS:kbusage

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The information in this article applies to:

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

When you are restoring a database created during an online backup, the log files
may not replay into the database being restored if the circular logging status
has been changed from disabled to enabled.

CAUSE
=====

In the following scenario, the log files will not be replayed:

1. Circular logging is enabled.

2. An online backup is made of the information store or directory.

3. Circular logging is disabled.

4. A restore of the information store or directory is made to the server.

Log files created after circular logging is disabled cannot be replayed into a
database created when circular logging was enabled. In most cases, there will be
a gap in the logfile sequence, and messages cannot be recovered from logs
residing on the drive.

WORKAROUND
==========

When circular logging is disabled, you must immediately perform a backup of the
information store and directory to be able to restore a database and replay the
log files that will begin to be created after circular logging is disabled.

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Keywords          : kbusage 
Technology        : kbExchangeSearch kbExchange500 kbExchange550 kbExchange400 kbZNotKeyword2
Version           : WINDOWS:4.0,5.0,5.5
Issue type        : kbprb

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