I think that need to provide more information about what you are doing when you get this error. This appears to be a LV error. 1)What version of LV are you using? What are you doing in TestStand when you get this error? 2)Is your TestStand sequence calling a VI from which this error is generated? If so what is this VI doing? 3)Can you isolate the source of this error to a particular VI that is using queues? 4)How often does the error occur? 5)The path of Queue Core.vi is \vi.lib\Platform\synch.llb\Queue Core.vi. Can you put some probes on the input of this VI to determine what inputs are causing this error? What are all of the inputs to this VI when the error occurs? 6)Is queue being created or destroyed? Is an element being added or removed from a que ue? 7)Is this your queue or a queue used by one of LV's VIs?
Unless someone has had this exact error, then it is going to be difficult to debug without more information. Clearly, the problem is easiest to solve if it is reproducible by others.