OK, I think I understand your issue.
Install the add-in again if it is not.
Open Outlook, if you do not see the icons on the toolbar close Outlook and open Windows Explorer. Browse to
\Program Files\Enterprise Vault\EVClient and double click the ResetEVClient.exe
Re-open Outlook. If the issue still persisits double click an archived item and see if the buttons show properly then.
Regards,