?In a new client the Queue object and/or the Client need a time zone object assigned to it, only then it is possible to start the queue.
To attach it to a new queue, right-click the queue in the Activities Window and select "Edit object". Go to the Attributes tab and at the bottom is a pulldown menu labeled "TimeZone:" Select a TZ object from this combo box. If you have nothing to select, you will need to create a TZ object in this client or client 0.
Go to the system overview and edit the client object. Add a TZ object to the Queue.