In Exchange 2007, circular logging is disabled by default. By enabling circular logging, you reduce drive storage space requirements. However, without a complete set of transaction log files, you cannot recover any data more recent than the last full backup. Therefore, in a normal production environment, circular logging is not recommended.

Procedure
To use the Exchange Management Console to enable or disable circular logging

1. Start the Exchange Management Console.

2. In the console tree, expand Server Configuration, and then click Mailbox.

3. In the work pane, right-click the storage group for which you want to enable or disable circular logging, and then click Properties. The Properties dialog box appears.

4. Select or clear the Enable circular logging check box.

5. Click OK.

6. To make your changes to the circular logging settings effective, restart the Microsoft Exchange Information Store service, or dismount and then mount all of the databases in the storage group.


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