On my Office Outlook Calendar, I am getting an error in server status (Calendar Error)

Signed in successfully at 8/5/2013 7:00:51 PM                                                                          

Mail: Last successfully refreshed at 7:01 PM.                                                                          
Calendar: Error at 7:01 PM.                                                                                            
Contacts: Last successfully refreshed at 7:01 PM.                                                                      

Errors :

Time: 8/5/2013 7:00:53 PM
Error in Calendar
Synchronization error.

Time: 8/5/2013 7:00:54 PM
Error in Mail
Error with Send/Receive.
There was an error synchronizing your folder hierarchy. Error : 800cce05.

Time: 8/5/2013 7:00:55 PM
Error in Mail
Error with Send/Receive.
Look for a log in the Sync Issues folder.

Time: 8/5/2013 7:00:55 PM
Error in Mail
Error with Send/Receive.
Look for a log in the Sync Issues folder.

Time: 8/5/2013 7:00:55 PM
Error in Mail
Error with Send/Receive.
Look for a log in the Sync Issues folder.

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