When you install Ofice 2010 and 2013 you get a extra option in your right-click menu to Sync Shared Folders.
I don't use this so I remove it, here's how..

Open regedit.exe

Start Menu -> Run -> regedit

Now in regedit browse to


You can to go to


then Edit -> Find -> {6C467336-8281-4E60-8204-430CED96822D}

and rename it to backup.{6C467336-8281-4E60-8204-430CED96822D}

and you are done.