Communicator contacts not updating
Presence information helps you to contact others and helps others to reach you.
Office Communicator provides a full set of person presence attributes that you can customize and make available to other contacts to help them communicate with you.
This is actually an issue with Communicator, not Outlook, but because the error shows up in Outlook, it gets blamed.
The fix is fairly easy: delete Communicator's contact database from the affected user's computer and wait for the updated version to be downloaded.
The legacy and full delta files are only downloaded when a new file is downloaded to the workstation.