Users were verifying that recent changes in the organization structure were accurately reflected in the Organization Chart on users’ My Sites, and found that the changes were not updated, even after full profile synchronization with Active Directory. Running the synchronization again resulted in no resolution and no error messages. When Checking the AD connection (Central Admin>Manage Profile Service>Configure Synchronization Connection), the previously configured connection string was missing.
As answered by Stanislaw Delost in this Technet thread http://social.technet.microsoft.com/Forums/sharepoint/en-US/80fb3c8f-a91a-461e-ad8b-52fc4a771118/synchronization-connection-missing?forum=sharepointadminprevious, one of the Forefront Identity Manager Services was not started. We believe the service failed to restart after a server reboot to apply Windows Server Updates.
If either of the Forefront Identity Manager Service and Forefront Identity Manager Synchronization Services are stopped, manually start the Forefront these services from services.msc
Run a full profile sync. Note: a full profile synchronization may take significant time and server resources, depending on your number of user profiles. For larger organizations, it may be more appropriate to run the sync outside heavy production hours.
Add “Check that the Forefront Identity Manager Service and Forefront Identity Manager Synchronization Service restart” to the list of items to check each time a reboot of the server is necessary.