Meeting Center Error
 

I install Office 2007, when I open a meeting, a Meeting Center Error window
pop out, it say "Invalid Account Number", it asking for Meeting Number and
PIN Code. I am not sure what is that. I can see a "Meeting Center" button
between Appointment and Scheduling. I check on other computer that have
Office 2007 install, but they don't have "Meeting Center" button. Is than
anyone know how to remove it? Thanks!