"The operation failed.an object could not be found.cannot directly book a resource for this meeting." We are hosting the Exchange 2003 server and most of the client are using Outlook 2007.Got the error when attempted to book a resource. I thought the solution is to uncheck "Automatically accept meeting requests and process cancellations" .Yes it did allow the meeting to be send through,but this will lead to another issue.Conflicting or double book on the meeting room. When this is unchecked,the other options are freezed."Automatically decline conflicting meeting requests" and "Automatically decline recurring meeting requests".

Do the clients have permissions to create meetings on those resource calendars? Are you using the Auto-Accept script or direct-booking?

Got the answer from previous thread.I thought all users can book the resource by default.Permission only need to be given if need to view/edit resource's calender.Thanks.