Named CALs can't be shared. By defenition a Named CAL is for a single named person. QlikView will only allow one Named CAL/Machine Name to access an application at a time. When the same user name tries to access from a different machine then it knocks the first one off. This is how the license is designed. They are assigned to one user only. If you want more people to have access to the QlikView application then you either need more Named CALs, Session CALs or Usage CALs.