Background Cleanup for a mailbox store is non-default

Topic Last Modified: 2007-01-08

The Microsoft® Exchange Server Analyzer Tool reads the following registry entry to determine the current value data for the Background Cleanup registry value:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\<ServerName>\Private-<MailboxStoreGUID>\Background Cleanup

If the Exchange Server Analyzer finds that the value data for Background Cleanup is set to any value other than 60,000 (decimal) or 0xEA60 (hexadecimal), a non-default configuration message is displayed. We recommend that Background Cleanup be set to the default value.

If the Background Cleanup value is set too high, the background cleanup process may not run frequently enough and many issues may be encountered. This includes the following:

Move mailbox may fail and an event 1205 with error code 0x4e3 may be logged.
Folder sizes and item counts shown in Exchange System Manager or Exchange Management Console may differ greatly from those shown by Microsoft Outlook®. In addition, database space occupied by these items may not be reclaimed.
Unread receipts for items that were deleted without being read may not be generated under certain circumstances.
Cleanup of old entries in the DeliveredTo table will not occur. The DeliveredTo table is used by the Exchange store to prevent the delivery of duplicate messages.

If the Background Cleanup value is set too low, the background cleanup process may cause unnecessary load on the server.

Caution:
Following the procedure in this topic to revert to the default configuration from a value that is too high can result in an increased load on the server until background cleanup has completed for all items that would have ordinarily been cleaned up at the default interval. Therefore, we recommend that you make these changes at a time during which users will be minimally affected. Additionally, if messages for which read receipts were requested have been deleted without being read and have not been cleaned up because of this issue, unread receipts will be generated for each of those messages after you correct this warning.

Caution:

Following the procedure in this topic to revert to the default configuration from a value that is too high can result in an increased load on the server until background cleanup has completed for all items that would have ordinarily been cleaned up at the default interval. Therefore, we recommend that you make these changes at a time during which users will be minimally affected. Additionally, if messages for which read receipts were requested have been deleted without being read and have not been cleaned up because of this issue, unread receipts will be generated for each of those messages after you correct this warning.

Important:
This article contains information about how to edit the registry. Before you edit the registry, make sure that you understand how to restore the registry if a problem occurs. For information about how to restore the registry, view the "Restore the Registry" Help topic in Regedit.exe or Regedt32.exe.

To revert to the default configuration

Open a registry editor, such as Regedit.exe or Regedt32.exe.
Navigate to: HKLM\System\CurrentControlSet\Services\MSExchangeIS\<ServerName>\Private-<MailboxStoreGUID>
Change the value of Background Cleanup to 60,000 (decimal) or 0xEA60 (hexadecimal).
Close the registry editor and restart the Microsoft Exchange Information Store service for the change to take effect.

Before you edit the registry, and for information about how to edit the registry, see the Microsoft Knowledge Base article 256986, "Description of the Microsoft Windows registry" (http://go.microsoft.com/fwlink/?linkid=3052&kbid=256986).