I have a user whose contacts keep multiplying in Outlook even when they are deleted locally. Exchange continues to sychronize all of the contacts back to the client, even duplicating them sometimes 10 fold. The problem arose after the user acquired a new mobile phone. All contacts have been deleted from the mobile device as well. You help is greatly appreciated.

Use Outlook in live mode - so not cached mode. Move the contacts to another folder. Then ensure that syncs. To find the duplicates, change the view to Category, then add the field "Created on". This will show the date. The duplicates will have almost identical time/date. Makes it easy to remove them. Simon.Simon Butler, Exchange MVP. http://blog.sembee.co.uk , http://exbpa.com/