Cannot see shared calendars anymore

I was having trouble with Outlook staying open. I adjusted the add-ins as noted in the knowledge base and it helped. When that problem occured I also had a problem seeing my associates calendars and task pad. The add-ins fix did not however give me the ability to see the calendars I used to see. My associates have tried re-sharing with me, but they are given a meesage from OUtlook stating that we are already sharing. Before I did the add-ins fix I was receving to my Inbox NET.Folders messages whenever they made new or updated changes. I have also noticed that under the FILE pulldown I no longer have "sharing" as an option.