I have an SBS 2011 server running exchange 2010. I have multiple users using outlook calendar to reserve a conference room. When one user reserves a time, another user goes in and reserves it at the same time. They should be getting a conflict message, but we are not. The users are using various versions of outlook (2003,2007,2010,2013).
Any assistance in configuring the calendar to throw a conflict message when the calendar is double booked would be of great assistance.