An Outlook user asked this question:
When I schedule a recurring meeting and the room is booked for one or more of the meetings, the room will decline the entire schedule of recurring meetings. How can I fix this?
This is not something an end-user can fix. The recurring event is declined because that is how the administrator has the Exchange server configured and you'll need to speak to the Exchange administrator.
If the administrator wants to change the settings and you are using Exchange Server 2010 or 2013, the Set-CalendarProcessing cmdlet is used to allow conflicts and to configure how many conflicts are allowed.
Set-CalendarProcessing -Identity "Room 2" -AutomateProcessing AutoAccept -AllowRecurringMeetings:$true -ConflictPercentageAllowed 25 -MaximumConflictInstances 3 -AllowConflicts:$true
In Exchange 2007 the Set-MailboxCalendarSettings cmdlet is used to allow conflicts and set the maximum number of conflicts and the percentage of conflicts allowed in a single recurring event.
Set-MailboxCalendarSettings -Identity "Conference Room" -AutomateProcessing AutoAccept -AllowConflicts:$true -AllowRecurringMeetings:$true -ConflictPercentageAllowed 25 -MaximumConflictInstances 3