sync with endnote web

Hi there, I’ve a problem with the endnote syncing. Up to last week everything was fine (Endnote X7.3.1, OSX10.9.5) but lately synchronizing with endnote web is caught in a loop. The status bar at the top keeps repeating “authorizing - retrieving account info - retrieving group sets - retrieving groups - retrieving references - sending updates”. After an hour or so I got suspicious so I checked endnote web and there everything seemed up-to-date. What could be wrong?

I would call tech support to discuss syncing problems.  Each one seems different.  

www.endnote.com/support