It is something to do my Proxy Server and the Exchange Update that reset couple of my settings.
For the Proxy Server issue, I have reapplied the Group Policy to all users.
By default Microsoft sets the Calendar Entries to show as Free or Busy when viewed by other people.
Please follow the instructions below to set Free/Busy options.
Outlook 2011 users must be granted "Reviewer" access to another person's calendar to be able open that calendar and view details.The thing is, the user can see anyone free/busy through the OWA. Finally, I found the answer for my problem with Free/Busy Scheduling in Outlook 2010 Calendar.I have been looking everywhere that I know about in Exchange 2010.Apart from the permission of viewing Free/Busy information, you need to mark your appointments as busy, free, or others.This article will guide you to show appointments in calendars as busy, free, tentative, or out of office in Microsoft Outlook.