We have a shared Outlook 2010 calendar in the office that we all use to create appointments. Now, randomly when I open up this calendar and try to Make A New Appointment, it is grayed out. I am still able to retrieve email at this time so I know my connection is good. After an hour or so, I am able to set appointments again. It happens just randomly and it goes away on its on. Its only affecting 1 PC here. Any thoughts?