Question : Exchange 2007 SP1 resource getting double booked by adding it as a required attendee

When a user creates a meeting in Outlook 2003 (Exchange 2007 SP1), they are adding a meeting room as a required attendee instead of a resource.  If that room was already properly booked as a resource and another user books the same meeting time but makes that room an attendee, the room will get technically get double booked.

I've tested this with Outlook 2003 clients and it will allow me to do it.  The same goes with Outlook 2007.  I even opened that calendar in OWA and it shows 2 meetings for the same time.
What is really neat is in OWA 2007, if I add a meeting room under the "Select Attendees"list, it comes back and says "Rooms are not allowed in the attendee list and have been moved to the rooms list." which is great!

Bsides educating the user community (which we know isn't always easy), is there a way to prevent a resource from getting booked as an attendee in Outlook?

My setup is the following:
Exchange 2007 SP1
CAS/HUB server
SCC mailbox cluster

Answer : Exchange 2007 SP1 resource getting double booked by adding it as a required attendee

I would definitely educate your end users on how to book a room, but I would also run this cmdlet against your Resource mailboxes:

Set-MailboxCalendarSettings -Allowconflicts $false

This will prevent anyone from double booking a room.