Sorry to hear you're having trouble with Box Sync.
Would you please file a ticket with our support team so that they can troubleshoot and help get this resolved?
Here is how to do that:
1) Make sure you're logged into www.box.com with your Box login and password
2) Hover over your name in top right corner of the page
3) Click "Help"
4) Click "Support"
5) Click "Submit a request"
Thanks for your patience and understanding while we work to resolve this.