Mind the online maintenance window!
The online maintenance is a crucial Exchange process that organize the databases, recover unused space and perform other housekeeping tasks. By default, Exchange Server runs maintenance tasks daily from 1:00 A.M. to 5:00 A.M. It is important not to let any other activity overlap in time with the regular online maintenance, such as backups.
The event 703 should occur, at least, every 2 days for each mailbox database:
Event Type: Information
Event Source: ESE
Event Category: Online Defragmentation
Event ID: 703
To use the Exchange Management Shell to set the maintenance schedule for a database, use one of the following cmdlets:
- set-MailboxDatabase –Identity 'DatabaseIdentity' –MaintenanceSchedule Schedule
- set-PublicFolderDatabase –Identity 'DatabaseIdentity' –MaintenanceSchedule Schedule