I have a few users who have an issue with their tasks being duplicated. This seems to be result of our migration from Exchange 2007 to Exchange 2010. Users are running on Windows XP. I have removed and re-created the Outlook profile and it seemed to work until the next day, now they are duplicated again. I pulled her mail up on my station with no issue, so has to do with something on her PC. I checked her Outlook profile, no data files exist.